Process for the preparation of graft copolymers

ABSTRACT

Process for the preparation of thermoplastic graft copolymers which comprises heating for about 15 seconds to 60 minutes, with mixing, a trunk copolymer of at least two monomers, at least one of said monomers providing amine-reactive sites taken from the group consisting of the anhydride group, e.g., maleic anhydride; a vicinal pair of carboxylic groups and a carboxylic acid adjacent to an alkoxycarbonyl group, wherein the alkoxy group contains up to 20 carbon atoms, and at least one of said monomers containing no amine-reactive sites, and at least one side chain polymer having per chain one active amine site taken from the group consisting of primary and secondary amines, the remainder of said side chain polymer being substantially unreactive with the reactive sites, e.g., amino-substituted polycaprolactam, polylaurolactam, polyethylene oxide, etc., of the trunk copolymer. The process provides control of the type and length of the side chain polymer grafted onto the trunk copolymer. Plastic graft copolymers are included, specifically those containing one or more side chain polymer types with the proviso that when only one type side chain polymer is present the side chain polymer contains only one nitrogen atom, said atom being found in the active amine site.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a process for the preparation of thermoplasticgraft copolymers and particularly a process wherein the graft copolymersare formed by reacting a trunk copolymer having reactive sites with aside chain polymer having an amine group reactive with the sites. Thisinvention also relates to graft copolymers.

2. Description of the Prior Art

Many grafting processes are described in the prior art. Generally, theterm "to graft onto" relates to a two step process whereby apolymerizable monomer is first blended with a polymer and then themonomer is polymerized, e.g., by free radical or ionic graftpolymerization, in the presence of the polymer. In the conventionalprocess this term to graft onto means a process in which the side chainpolymer is grown in the presence of the dead or preformed polymer. Inthe conventional grafting process, electron irradiation, peroxidetreatment, etc. are used to activate sites on the polymer chain forsubsequent polymerization of the monomer and attachment to the sites.Typical of prior art relating such conventional grafting processesinclude U.S. Pat. Nos. 3,136,738; 3,388,186; 3,465,059; 3,676,190 andBelgian Patent Nos. 780,964; 780,965 and 780,966. U.S. Pat. No.3,136,738 describes the grafting onto a vinyl backbone copolymer in thepresence of catalysts a caprolactam. The polycaprolactam is grown as aside chain onto the backbone polymer at the active sites. U.S. Pat. Nos.3,388,186 and 3,465,059 describe graft copolymers having backbone chainscontaining recurring ethylenic units and side chains containingcarboxy-terminated polyamide groups, the graft copolymers being formedby hydrolytically polymerizing in the melt a polyamide precursor such ascaprolactam or laurolactam in the presence of a preformedethylene/acrylic acid, salt or ester copolymer. U.S. Pat. No. 3,676,190discloses various type backbone polymers, preferably vinyl-type andvinylidene-type polymers and copolymers subjected to the action of ozoneand onto the polymer is grafted at least one polymerizable ethylenicallyunsaturated monomer. The Belgian patents teach that random copolymers ofethylene and minor amounts of maleic anhydride can be reacted withalcohols and amines; for example, a polyethanol amine. These Belgianpatents, however, describe bridged or crosslinked polymers where thebridging agents contain two or more reactive sites.

U.S. Pat. No. 3,676,400 relates to blends of high-amine-end polyamideswith acidic olefin copolymers. The olefin copolymers can be derived fromethylene and monoethylenically α,β-unsaturated monocarboxylic ordicarboxylic acids such as acrylic, methacrylic, maleic, fumaric acids,etc. Each polyamide molecule has on the average more than one activeamine site which can react with the reactive sites of the trunkcopolymer if such reactive sites are present. The reaction productcontains crosslinks which are not desired in the graft copolymers of thepresent invention.

None of the prior art suggests grafting onto a trunk copolymer apreformed side chain polymer having one amine group active with sites onthe trunk copolymer to produce a thermoplastic or soluble polymer.

The value of the present invention can be more fully understood whengraft copolymers having two different types of side chains are prepared.If conventional prior art techniques are used, either copolymer sidechains are obtained from mixed comonomers or when the monomers are usedto form a graft copolymer in two steps either the active sites on thetrunk copolymer are blocked by the first monomer or many side chains areformed containing grafts of the second monomer on the chains previouslyformed from the first monomer. In contrast, by the process describedbelow, two or more types of side chain polymers may be grafted onto atrunk copolymer simply by mixing the preformed polymer side chains atthe time the grafting reaction occurs.

SUMMARY OF THE INVENTION

According to one aspect of this invention, there is provided a processfor the preparation of thermoplastic graft copolymers which comprisesheating for about 15 seconds to 60 minutes, with mixing, (1) a trunkcopolymer of at least two monomers, at least one of said monomersproviding amine-reactive sites taken from the group consisting of ananhydride group, a vicinal pair of carboxylic groups and a carboxylicgroup adjacent to an alkoxycarbonyl group, wherein the alkoxy groupcontains up to 20 carbon atoms, and at least one of said monomerscontaining no amine-reactive sites, and (2) at least one side chainpolymer having per chain one active amine site taken from the groupconsisting of primary and secondary amines, the remainder of said sidechain polymer being substantially unreactive with the reactive sites ofthe trunk copolymer. The graft copolymer produced is thermoplastic andis not crosslinked.

According to another aspect of this invention, there is provided athermoplastic graft copolymer consisting essentially of a trunkcopolymer derived from at least two monomers, at least one of saidmonomers providing amine-reactive sites taken from the group consistingof an anhydride group, a vicinal pair of carboxylic groups and acarboxylic group adjacent to an alkoxycarbonyl group, wherein the alkoxygroup contains up to 20 carbon atoms, and at least one of said monomerscontaining no amine-reactive sites, and at least one type side chainpolymer linked to said reactive sites through amide or imide linkages,said side chain polymer being derived from a short chain polymer havingfrom about 5 to 50 repeat units and containing one active amine siteselected from the group consisting of primary and secondary amines, theremainder of the side chain polymer being substantially unreactive withthe amine-reactive sites of the trunk copolymer, with the proviso thatwhen only one type of side chain polymer is present the side chainpolymer contains only one nitrogen atom, said atom being found in theactive amine site.

The term "trunk copolymer" as employed herein includes thepolymerization product of at least one polymerizable monomer which hasno amine-active sites, e.g., ethylene, vinyl monomers such as vinylacetate, styrene, vinyl chloride, etc., and at least one polymerizablemonomer which provides amine-active sites, e.g., maleic anhydride.Included in the term is a copolymer having grafted thereon a monomerwhich provides the amine-active sites, e.g.,ethylene/α-mono-olefin/1,4-hexadiene/maleic anhydride copolymer.

The term "side chain polymer" as employed herein includes thepolymerization product of a polymerizable monomer which contains oneactive amine site per chain, said amine site being subsequently attachedto the amine-active sites of the trunk copolymer. The active amine siteis generally on one end of the side chain polymer while the other endsor substituent groups of the side chain polymer are substantiallyunreactive with the reactive sites of the trunk copolymer. The extent towhich there may be more than one reactive site per chain is determinedby the degree of crosslinking obtained in a specific case; i.e., theamount of additional reactive sites per chain, over one per chain, mustbe so small that the graft copolymer is not substantially cross-linked.

By the process of the invention at least one side chain polymer type canbe attached to the amine-reactive sites of the trunk copolymer. Two ormore different side chain polymer types, however, can be present in thegraft copolymer. Different side chain polymer types refers to at leasttwo side chain polymers, e.g., polycaprolactam, polylaurolactam,polyethylene oxide, polypropylene oxide, and other side chain polymersdescribed below which for purposes of this invention are differentchemical structures. Different side chain polymer types does not referto a mere difference in molecular weight of a particular side chainpolymer type such as polycaprolactam, etc.

DETAILED DESCRIPTION OF THE INVENTION

Thermoplastic graft copolymers are prepared in accordance with theprocess of this invention by reacting a trunk copolymer havingamine-reactive sites with at least one side chain polymer having aboutone active amine site of primary or secondary amines; the other groupsor ends of the side chain polymer are substantially unreactive with thereactive sites on the trunk copolymer. In the final graft copolymer thetrunk copolymer content ranges in an amount of about 25 to 95 percent byweight and the side chain polymer content ranges from about 5 to 75percent by weight. The trunk copolymers contain, on a number average,about 300 to 50,000, preferably 500 to 20,000, chain atoms, and a numberof amine reactive sites occurring, on the average, at a frequency ofabout one to 200 per 1000 chain atoms of the trunk copolymer. On theaverage there will be at least one active site per trunk copolymerchain. The side chain polymer will, in general, be shorter than thetrunk copolymer, ranging in length from about 25 to 1,000 chain atoms,preferably about 30 to 300 chain atoms.

The trunk copolymers must be sufficiently stable to withstand heatingduring the grafting of the side chain polymer. They should also be freefrom hydroxyl, primary amino, and secondary amino groups which can reactwith the amine reactive graft sites to form thermostable crosslinkscausing a loss of the desired thermoplasticity.

The amine-reactive sites on the trunk copolymers are provided bymonomers which are either copolymerized during the preparation of thetrunk copolymer or are grafted onto a previously existing polymer.

Copolymerization of a monomer providing the amine reactive site withother monomers is possible when the other monomers are polymerizable byconventional free radical catalysis. α-olefins (such as ethylene,propylene, 1-butene; alkyl acrylates and methacrylates (such as methyl,ethyl and butyl); conjugated dienes (such as 1,3butadiene, isoprene);other dienes (such as 1,4-hexadiene); styrene, methyl vinyl ether,methyl vinyl sulfide, acrylonitrile, vinyl acetate, vinyl chloride, andthe like are well known examples of suitable comonomers.

Free radical polymerizable monomers which can be incorporated into thetrunk copolymer to provide the amine reactive sites, have the formulae##STR1## where X and Y are independently selected from H, Cl, C₁ -C₈alkyl and phenyl with the proviso that one of X and Y must be H and W isH, C₁ -C₁₀ alkyl, phenyl, naphthyl or substituted phenyl or naphthylwhere the substituents are C₁ -C₁₀ alkyl, halogen, and C₁ -C₁₀ alkoxygroups, and V is a radical containing C₂ -C₁₂ alkenyl and having acopolymerizable double bond.

Compounds representative of formula (a) include maleic anhydride andcitraconic anhydride. Compounds representative of formula (b) includemaleic acid, citraconic acid, fumaric acid, mesaconic acid, andmonoesters of maleic and fumaric acid, including the methyl, ethyl,isopropyl, propyl butyl, tert-butyl, amyl, isoamyl, hexyl, octyl, decyl,phenyl, 1-naphthyl, 2-naphthyl, 2-methylphenyl, 2-ethylphenyl,2,5-dimethylphenyl, 4-isopropylphenyl, 4-butylphenyl,3,5-dimethyl-3-propylphenyl, 3-decylphenyl, 4-tetradecylphenyl,4-hexadecylphenyl, 4-octadecylphenyl, 2-chlorophenyl, 4-methoxyphenyl,2-chloro-1-naphthyl, 4-chloro-1-naphthyl, 6-chloro-1-naphthyl,7,8-dichloro-1-naphthyl, 4-bromo-1-naphthyl, 7-chloro-2-naphtyyl,4-methyl-1-naphthyl, and 1-propyl-2-naphthyl. Compounds representativeof formula (c) include alkenyl succinic anhydrides, e.g., 3-ethenylsuccinic anhydride, 3-ethenyl, 4-methyl succinic anhydride, 3-allylsuccinic anhydride, 3-isopropenyl succinic anhydride, 3-(2-butenyl)succinic anhydride, 3(4-pentenyl) succinic anhydride, etc. Also usefulare itaconic acid, its anhydride and monoesters.

The copolymerization reaction to form an ethylene containing trunkcopolymer can be carried out most advantageously in a pressure reactorat a temperature of 90°-250°C. and a pressure of 1600-2200 atm. Thepolymerization temperature is preferably maintained at about 145°C. andthe pressure at 1800-2000 atm. Usually, the polymerization process iscontinuous, the monomer, optionally a solvent such as benzene, and theinitiator being introduced at a controlled rate, and the reactionproduct being continuously removed. A stirred autoclave such asdescribed in U.S. Pat. No. 2,897,183 to Christl et al. can be used.Suitable free-radical polymerization initiators include organicperoxides, for example, lauryl peroxide, and di-t-butyl peroxide;peresters, such as t-butyl peracetate and t-butyl peroxypivalate; andazo compounds, such as azobisisobutyronitrile.

A representative trunk copolymer is a random copolymer having a meltindex of about 0.3 to 100 grams/10 min. and consisting essentially ofpolymerized ethylene, an alkyl acrylate selected from methyl and ethylacrylate, and from 0.0025-0.077 mole/100 grams of polymer of a monoalkylester of a 1,4-butene dioic acid in which the alkyl group of the esterhas 1 to 6 carbon atoms, each 100 grams of copolymer having from about0.64-0.80 mole of (--CO₂ --) units. Copolymers of ethylene, methylacrylate, and ethyl hydrogen maleate corresponding to the above havecompositions such as the following:

    Mole %                                                                                                       Ethyl                                                                         Hydrogen                                       Ethylene     Methyl Acrylate   Maleate                                        ______________________________________                                        71.2         28.7              0.1                                            57.8         42.1              0.1                                            74.4         22.0              3.6                                            61.4         34.4              4.2                                            ______________________________________                                    

Another representative trunk copolymer is an alternating copolymerhaving repeating units consisting essentially of --A--B-- where Brepresents ethylene units and A represents units selected from at leastone C₁ -C₈ alkyl acrylate and an acrylic cure-site monomer having theformulae (a) or (b) described above. The copolymerization is done insolution at -10°C. to about 200°C. in the presence of a free radicalinitiator and BF₃ at pressures sufficient to keep the BF₃ complexed withthe alkyl acrylate (generally 0.703 to 703 kg./sq. cm. gauge). SeeLogothetis U.S. Ser. No. 233,741, filed Mar. 10, 1972.

An important class of copolymers which cannot be made with free radicalcatalysts includes EPDM rubber. These copolymers are prepared by usingthe well known Ziegler or coordination catalysts which are combinationsof transition metal compounds (usually vanadium or titanium compoundssuch as VOCl₃, VCl₄, vanadium trisacetylacetonate, and titaniumtetrachloride) and Group I-III organometallic reducing agents (such asalkylaluminum chlorides and bromides, lithium aluminum tetraalkyls,aluminum trialkyls). EPDM rubber is made by copolymerizing ethylene andpropylene with at least one non-conjugated hydrocarbon diene, e.g.,1,4-hexadiene, 5-propenyl-2-norbornene, 5-ethylidene-2-norbornene,5-methylene-2-norbornene, dicyclopentadiene as described in Gresham andHunt U.S. Patent 2,933,480; Tarney U.S. Pat. No. 3,000,866; GladdingU.S. Pat. No. 3,093,620; Gladding and Robinson U.S. Pat. No. 3,093,621;Adamek, Dudley and Woodhams U.S. Pat. No. 3,211,709; and Nyce U.S. Pat.No. 3,151,173. One of the double bonds is usually substantially lessreactive than the other; incorporation of the diene then leads to amonomer unit having the less reactive double bond in the side chain.After the copolymer has been formed, single monomer units such as thosedescribed above in formulae (a) and (b) which have amine reactive sitescan be grafted to the EPDM by thermal addition to the unsaturated sidechains. A typical trunk copolymer can be represented by the followingformula which illustrates the case of the addition of a single maleicanhydride group on an ethylene/α-monoolefin/1,4-hexadiene copolymer##STR2## wherein the wavy lines represent the polymer chain. Thisstructure can be achieved by reacting maleic anhydride with theethylene/α-monoolefin/1,4-hexadiene copolymer. The hydrocarbon copolymermay also include small amounts of units of a direactive non-conjugateddiene as in the ethylene/propylene/1,4-hexadiene/2,5-norbornadienecopolymer, as well as other copolymers described in Campbell and ThurnU.S. Pat. No. 3,819,591.

Propylene is normally selected as the α-monoolefin in preparing sidechain unsaturated elastomeric ethylene copolymers because of itsavailability and low cost. Higher α-monoolefins (C₄ -C₁₈) are useful,also; 1-butene, 1-hexene, and 1-dodecene are examples. The α-monoolefinsmay be omitted completely, making an ethylene/hexadiene copolymer.

The graft addition of amine reactive monomers described above, e.g.,maleic anhydride and ethyl hydrogen maleate, is convenientlyaccomplished by heating a blend of the copolymer and amine reactivemonomer within a range of about 225°-400°C., above the melting point ofthe trunk copolymer and side chain polymer. A process of this type isdescribed in detail in Caywood U.S. Pat. No. 3,884,882. Internal mixtureor extruders are suitable. Exposure to maleic anhydride vapor should beminimized on account of its toxicity and potential for causing severeeye damage. Unreacted maleic anhydride can be removed from the graftproduct by aqueous extraction or by dissolution in hexane, a nonsolventfor maleic anhydride.

In preparing the trunk copolymer, for example, ethylene and ethylenicmonomers having carboxylic functionality may be copolymerized, thecomonomers being randomly interconnected through C--C linkages andcomprising 70-99 percent by weight of ethylene. The carboxylicfunctionality is taken from the group consisting of the anhydride group,a vicinal pair of carboxylic groups and a carboxylic group adjacent toan alkoxycarbonyl group, wherein the alkoxy group has up to 20 carbonatoms. Examples of specific trunk copolymers are: ethylene/maleicanhydride, ethylene/(lower monoalkyl C₁ to C₄) maleate, ethylene/(lowermonoalkyl C₁ to C₄) fumarate, ethylene/(lower monoalkyl C₁ to C₄)itaconate, ethyl acrylate/maleic anhydride, ethyl acrylate/monoethylfumarate, styrene/maleic anhydride, styrene/monoalkyl (C₁ to C₄)maleate, styrene/monoalkyl (C₁ to C₄) itaconate, alkyl vinylether/maleic anhydride, vinyl chloride/maleic anhydride, and otherscontaining three and four components, e.g., alternating ethylene/ethylacrylate/allyl acrylate/maleic anhydride, alternating ethylene/ethylacrylate/ethylene diacrylate/maleic anhydride, ethylene/maleicanhydride/3-methyl butene or vinyl acetate, ethylene/vinylmonomer/monoethyl maleate or monoethyl fumarate, ethyl acrylate/butylacrylate/monoethyl fumarate, vinyl chloride/vinyl acetate/maleicanhydride, etc.

The side chain polymers linked to the reactive sites can be of the samekind or of different types of polymers set forth below. The side chainpolymers are short chains having about 5 to 50 repeat units. At least 80percent of the side chain polymers have one reactive end group ofprimary or secondary amines, preferably primary amine, and the otherends or substituent groups are substantially unreactive, e.g., alkylcontaining 1 to 18 carbon atoms, amide, aryl, carboxylic acid, etc.Examples of side chain polymers that can be linked to the reactive sitesinclude: (1) polymers of lactams containing 3 to 12 carbon atoms, e.g.,polycaprolactam, polylaurolactam, other lactams such as those made fromβ-alanine (nylon 3) from γ-aminobutyric acid (nylon 4), ω-aminovalericacid (nylon 5) and similar polyamides from ω-amino acids containing 7,8, 9, 10 or 11 carbon atoms (anthranilic acid is also useful); (2)copolymers of said lactam containing 3 to 12 carbon atoms, e.g.,copolymers of caprolactam and laurolactam as well as the other lactamsdescribed above; (3) polymers of organic oxides containing 2 to 16carbon atoms, e.g., ethylene oxide, propylene oxide, 1,2-butyleneepoxide, 1,4-butylene epoxide, styrene oxide, 1,2-diphenyl ethyleneoxide, dioxolane; (4) copolymers of said organic oxides containing 2 to16 carbon atoms; (5) polymers of styrene; (6) polymers of substitutedstyrenes (1 to 4 carbon atoms); (7) copolymers of styrene andsubstituted styrenes; (8) polymers of acrylates; (9) polymers ofmethacrylates; (10) copolymers of acrylates and methacrylates; and (11)polymers of lactones.

The graft copolymers of this invention, for example, may be representedas V_(k) W_(l) X_(m) Y_(n) Z_(p) where V represents the dominantmonomer, W the modifying monomer for the trunk copolymer, X the monomercontaining the reactive sites, Y the repeat unit used in one type ofside chain, and Z the repeat unit used in another type of side chain.

The graft copolymer can be produced by a three step process in which (a)V_(k) W_(l) X_(m) is produced, (b) Y_(n) and/or Z_(p) is produced, and(c) the product V_(k) W_(l) X_(m) Y_(n) or V_(k) W_(l) X_(m) Y_(n) Z_(p)is produced by a simple molten phase or solution reaction.

When the value of subscript k is greater than the value of subscript l,the monomer V is viewed as the dominant monomer. The value of subscriptl, in fact, may be zero. W is considered to be sufficiently general toinclude one or more modifying monomers. X is the monomer which providesthe reactive site. Y represents the monomer from which the side chainpolymer is produced and this may be a copolymer as well as ahomopolymer. Y_(n) contains one primary or secondary amine group,generally on one end. At least 80 percent of the molecules, Y_(n),contain one amine group. Substantially none of the molecules Y_(n)contain more than one amine group, or other groups which are reactivewith the reactive site associated with the monomer, X, since the meltreaction would then produce a crosslinked product.

In an important embodiment the process can be used to prepare graftcopolymers represented by the formula: V_(k) X_(m) Z_(p), wherein Vrepresents ethylene, ethyl acrylate, styrene, etc.; X represents afunctional ethylenic compound; e.g., maleic anhydride, mono(lower alkylC₁ to C₄) maleate, fumarate and itaconate; V_(k) and X_(m) are randomlyinterconnected through C-C linkages; Z represents a polyamide side chainof the formula: ##STR3## Z_(p) is attached to X through an amide orimide group linkage; R₁ is hydrogen or C₁ to C₁₈ alkyl; R₂ is C₁ to C₁₈alkyl, aralkyl, e.g., benzyl; aryl, e.g., phenyl; or R₁ and R₂ takentogether constitute a 5 or 6-membered ring; k, m, p and r are integers(though analytical data may give average fractional values for k, m, andp); the ratio of k:m is in the range of 4:1 to 200:1 and in suchadditional relationship that the weight ratio of V_(k) :X_(m) is in therange of 99:1 to 70:30; r is 3 to 11, preferably 5 or 11; and p is inthe range of about 4 to about 29, preferably 5 to 9. The value of rdefines the type of polyamide used.

The subscripts k and m in the above formula represent the number ofrespective ethylenic, acrylic or styrene monomer units and the number ofmonomer units which provide the active site, e.g., maleic anhydride, inthe trunk copolymer. It is apparent that no more than one polyamidesegment is attached to any X-site, but not every X-site need have a Yside chain.

When a polyamide is used as the side chain polymer the amount by weightof the polyamide component depends on several factors, e.g., frequencyof attachment of side chains, number of units per side chain andmolecular weight per unit. The proportion of polycaprolactam isgenerally in the range of 20 to 75 percent by weight of the graftcopolymer, preferably 33 to 50 percent by weight; the proportion ofpolylaurolactam is generally in the range of 15 to 60 percent by weight,preferably 15 to 35 percent by weight.

Preferably the preformed side chain polyamides are derived fromoligomeric polycaprolactam or polylaurolactam, or copolymers of theselactam. These oligomeric polylactams have one reactive primary amino endgroup and one nonreactive end group. They are prepared by reacting thelactam with an amine, corresponding to R₁ NHR₂, where R₁ and R₂ are H,C₁ to C₁₈ alkyl, benzyl and C₅ to C₆ cycloalkyl with the proviso that R₁and R₂ are not both H and R₁ and R₂, when taken together, constitute aring such as in C₄ to C₅ alkylene or a ring containing a heteroatom asin 3-oxapentylene, in an amount designated to produce an oligomer havinga predominant average degree of polymerization in the range of about 5to about 60, preferably 6 to 10, more preferably 6 to 8. This reaction,carried out at a temperature in the range from about 250°C. to about300°C. can be represented on a theoretically quantitative basis asfollows: ##STR4## R₁, R₂, r and p are as defined above.

Optionally, a small amount of water can be added as a reaction promoter,in which case a free carboxylic acid end group, in small porportioncorresponding to the amount of water, is produced alternatively to theamido end group. In practice the reaction may not be quantitative sincethe product may contain unreacted lactam and amine, and a small amountof a mixture of oligomers having degrees of polymerization below 5.Since the unreacted starting materials and the lower molecular weightoligomers are readily soluble, they may be removed by solvent extractionand the remaining oligomeric mixture then used in preparing the graftcopolymer. This ability to control the quality of the side chain polymeris an important attribute of this invention. The average degree ofpolymerization of the residual polylactam is determined through analysisby standard titration procedures for amino end groups in terms ofequivalents per weight of sample.

The graft copolymers can be prepared in various ways. Convenient waysdescribed herein can be identified as (1) the anhydride route, for usewith ethylene/maleic anhydride and other anhydride-containing trunkcopolymers, and (2) the vicinal acid-acid or acid-ester route, for usewith trunk copolymers having diacid or monoester of vicinal dicarboxylicacid substituents, respectively.

The anhydride route, which is preferred, involves simply heatingtogether with mixing the trunk copolymer having carboxylic anhydridegroups, preferably maleic anhydride, and the amino oligomer in themolten state, at a temperature in the range 75°-250°C., preferably atabout 225°C., or in solution at a temperature of 75°-100°C. or higher.The heating temperature is above the melting point of the trunkcopolymer and the reactive polymer. The time of reaction, which isdependent upon the temperature and rate of mixing, can vary from about15 seconds to 60 minutes in the melt, preferably 1 to 10 minutes, andfrom 15 seconds to five hours in solution, preferably 1 to 10 minutes.Reaction in the melt, an especially preferred procedure, canconveniently be carried out on a roll mill, in a melt extruder, or ininternal mixers having convoluted rollers, sigma blades, etc., using atemperature that will give short reaction time and as many passes asnecessary to insure complete reaction. Completeness of reaction can bejudged by the appearance of the product, good clarity in the meltindicating essentially complete reaction. With a roll mill as thereactor, the backbone copolymer and oligomer can be premixed or mixedduring reaction on the mill; and because of the exposure it may bedesirable to include stabilizing agents such as inhibitors orantioxidants, or to carry out the operation in a protective atmospheresuch as nitrogen. With an extruder as the reactor, premixing isdesirable. On the basis of IR analysis of the products, aninterpretation of the course of the thermal reaction is that it mayproceed through initial formation of amic acids to ultimate formation ofamide or imide linkages between the backbone copolymer and the polyamideside chains, e.g.,: ##STR5## The amount of amino oligomer used can varyfrom a stoichiometrical deficiency to an equivalent amount, dependingupon the extent of side chain substitution desired on the graftcopolymer.

The vicinal acid-ester route has in general the operatingcharacteristics of the anhydride route, i.e., it can be carried out insolution or in the melt for reaction times similar to those for theanhydride route described above. The graft copolymer is believed to beobtained by attachment of the oligomeric polyamide side chain to thebackbone copolymer through imide linkages (with elimination of alcohol)which may be derived through intermediate formation of amic acids, e.g.,##STR6## or by prior conversion of the vicinal acid-ester by loss ofalcohol to an anhydride and reaction of the latter with the aminooligomer as described above. The description above of the anhydrideroute as carried out on a roll mill or in an extruder applies as well tothe vicinal acid-ester route conducted in the same way.

The reaction of the amine group with the anhyride is fast, so that theeffective reaction rate of polymers containing these groups is limitedby other factors such as the rate of mixing. When two polymers aredissolved in solution, separately, and the two solutions pouredtogether, rapid intimate mixing is obtained. The reaction can becompleted in about 1 minute or less at about 100°C. As the temperatureof the solution is increased the reaction can be completed in less than1 minute, e.g., down to about 15 seconds.

When the two polymers are mixed in the melt, they are generallyincompatible before the reaction takes place. The mixture is one of twoincompatible liquids, and the reaction takes place, primarily, at theinterface. As the reaction progresses, the melt blend becomes a singlephase and the reaction goes very rapidly to completion, even at melttemperatures as low as about 100°C. Blended mixtures of the carboxylicbackbone copolymers and the amino oligomeric polyamides arecharacteristically cloudy in the melt prior to completion of thegrafting reaction. The mixtures, in contrast to the graft copolymers,can be extracted with suitable solvents to isolate the backbonecopolymers and the lactam oligomers unchanged and in relatively purestate.

The graft copolymers are identified by the chemical reaction of thereactive site of the trunk copolymer with the reactive amine group ofthe side chain copolymer. This may be demonstrated by showing that thereactive site on the trunk copolymer has been reacted to form some otherchemical entity. In the specific case of the anhydride group, thereaction may be demonstrated by known analytical methods.

For example, the progress of grafting can be followed by infraredspectroscopy. When the starting trunk polymer contains 5-membered,cyclic anhydride active sites, the disappearance of either one or twocharateristic absorption bands at 5.4 microns or at 5.6 micronsindicates that grafting is taking place. The proportion of the anhydridegroups in the starting trunk polymer can be determined by forming apolymer film of known thickness and examining the infrared spectrum ofsuch film. It has been found experimentally that 0.28 absorptionunits/0.025 mm at 5.4 microns or 2.2 absorption units/0.025 mm at 5.6microns correspond to 10 weight percent anhydride. The absorption unitsare read directly from an infrared spectrogram.

Similarly, when the starting trunk copolymer contains vicinal carboxyland alkoxycarbonyl groups, the characteristic infrared absorption bandlies at 5.9 microns. Assuming the vicinal carboxyl and alkoxycarbonylgroups to be derived from ethyl hydrogen maleate, the characteristicabsorption will be 1.1 absorption units/0.025 mm for every 10 weightpercent maleate present. Such analytical techniques would not bepractical in the case of a starting copolymer containing vicinalcarboxyl groups. However, the concentration of carboxyl groups can bereadily determined by simple titration.

The graft copolymer product can be characterized by several techniques,which show the presence of polyamide side chains, the degree ofpolymerization of the polyamide side chains, and the chemical identityof the polyamide, to name a few. Certain physical characteristics oftenare also helpful to show that a graft copolymer has been obtained.

The presence of polyamide is shown by infrared absorption at 6.0 microns(amide carbonyl). Other useful wave lengths include 6.4 microns (--NHbending) and 3.0 microns (--NH stretching). The proportion of polyamideis determined by Kjeldahl analysis for percent N.

The polyamide can be chemically identified by heating a sample of agraft copolymer with a mineral acid, for example, a sulfuric orhydrochloric acids, to about 200°C. or more. Under these conditions, thepolyamide chain degrades to the starting lactam. Since ε-caprolactam andω-laurolactam are volatile, they can be isolated and identified by anyconvenient technique of qualitative analysis.

Direct measurement of graft efficiency by extraction of unboundpolyamide is difficult since solvents for polyamides also attack graftcopolymers and most truck copolymers as well. Titration of the graftcopolymers for reactive functionality provides no more than roughestimates of graft efficiency.

Determination of the increase of molecular weight due to grafting is aconvenient technique. This is usually done by gel permeationchromatography of 0.5 percent graft copolymer solutions in m-cresol at100°C. on porous polystyrene-packed columns.

A good indication that grafting has taken place is the torsion modulusof the product, especially at 100°-150°C. While the polyamide graftedcopolymer will have a fairly high modulus (e.g., 10⁷ -10⁸ dynes/sq. cm.,ungrafted material will flow in that temperature range.

The graft copolymers are identified as such, rather than mere mixturesof the trunk copolymers and polymers of the side chain type by a varietyof tests. These include clarity of the melt, solubility properties, andin some cases, by their retention of elastic modulus at elevatedtemperatures. Blends of two polymers or of a polymer an oligomer aregenerally not compatible; molten blends consist, in general, of twoimmiscible phases. Such two phase systems are hazy because of therefractive index difference between the two types of polymers. When sucha system changes from opaque or hazy to a clear product, it is strongevidence that an intimately joined graft polymer has been produced. Thesame optical test can be applied to samples in film form in the solidstate at room temperature. Another well-known method for discriminatingbetween a blend and a graft depends upon different solubility of thetypes of polymers involved. A third method is based on the very reasonfor making certain types of graft copolymers, i.e., the retention ofphysical properties at elevated temperatures. For these types, the blendwill tend to lose its stiffness and to flow as the temperature isincreased; some graft copolymers will better retain their stiffness andshow less creep as the temperature is increased.

With regard to polyamide resins knowing the average degree ofpolymerization (DP) of each starting side chain polymer, it is possibleto plot DP versus the peak melting point of each resulting graftcopolymer, as determined with a differential scanning calorimeter (DSC).It has been observed that the peak melting point increases as the DP ofthe side chains increases. Such a plot can serve as a calibration curvewhich can be used for the determination of the DP of the grafts in thecopolymers of the present invention.

The polyamide graft copolymers must be conditioned for testing by firstheating to 250°C., then cooling at the rate of 10°C. per minute to 50°C.During the test, the sample is heated at the rate of 10°C. per minute.

DSC techniques are discussed in Thermoanalytical Methods ofInvestigation, by P. D. Garn, Academic Press, New York, 1965.

Another convenient and somewhat related technique for correlating the DPof the grafted polymer side chain with its melting point is differentialthermal analysis (DTA). The sample also must be preconditioned and isheated during the test at the rate of 20°C. per minute. The details ofthe DTA technique are described in Differential Thermal Analysis, R. C.MacKenzie, Editor, Academic Press, New York, 1970; especially in Chapter23, by C. B. Murphy, dealing with polymers, Vol. I, pp. 643-671.

The process provides control of the type and length of the polymer sidechain grafted onto the trunk copolymer. From the specific type of trunkcopolymer the average frequency of possible reactive graft sites can beradily determined by the fraction, e.g., on a molar basis, of monomermolecules providing the reactive sites which are polymerized into thetrunk copolymer. Since the polymeric side chains are preformed prior toreacting with reactive sites on the trunk copolymer excellent control ofthe graft copolymer is achieved. Thus there can be prepared a polymerside chain having either a narrow or broad molecular weightdistribution. The polymer side chains of various distributions can bemade at various times and then grafted at different times. It ispossible to graft two or more different types of polymer side chains bymeans of the process. The thermoplastic graft copolymer prepared isrelatively uncontaminated with ungrafted side chain polymer which may bea major problem in conventional free radical graft polymerization.

The advantage of this process in providing control of the side chainpolymers is illustrated as follows: For one particular use, it may bedesirable to have the side chain polymers of sufficient length so thatthese side chains can crystallize. Such a use was described to provideimproved properties at elevated temperatures. For another use a certaintype of side chain may be needed, but it may be important that the sidechain is not long enough to provide a substantial amount ofcrystallization at room temperature. Such a case is found withpolyethylene oxide side chains. For such chains, good anti-staticbehavior is obtained when the chains are mobile, i.e., non-crystalline.When the side chains of such a monomer contain more than about 80 chainatoms, the side chains will crystallize at room temperature and losetheir good anti-static behavior.

The graft copolymers can be prepared with selected physical propertieswhich make them useful in items such as flexible films and flexibletubing. The grafted products may have characteristic retention ofmodulus at elevated temperatures, a feature which extends the usefulnessof films and tubes into temperatures which cause failure of articlesmade with merely blended mixtures of polyethylene and polyamides. Usefultoughness (impact resistance) at low temperatures can also be achieved.In certain uses, e.g., tubing for automotive applications, resistance tozinc chloride is most desirable. Graft copolymers having polylaurolactamside chains have been found especially resistance to zinc chloride.Another unanticipated property of considerable value is the reducedwater absorption shown by the graft copolymers in comparison withmaterials such as homopolycaprolactam (Nylon-6) or blends of Nylon-6with polyethylene.

The graft copolymers can be formed into shaped articles. Specificallygraft copolymers such as those containing side chain polyethylene oxidepolymers can be incorporated into a hydrocarbon polymer, e.g.,polypropylene, to provide a high degree of anti-static behavior topolypropylene fiber. Ethylene graft copolymers can be blended withrelatively low molecular weight thermoplastic resins to produce a hotmelt adhesive. It has been found that the adhesive has greaterresistance to failure at elevated temperatures than does an adhesivebased on ungrafted ethylene copolymers. By grafting a polymethylmethacrylate side chain onto rubbery copolymers such as ethylene/vinylacetate copolymers an impact modifier for a hard polyvinyl chloridematrix is providied.

EXAMPLES OF THE INVENTION

The following procedures and examples wherein the percentages and partsare by weight illustrate the invention. The temperatures are in degreescentigrade unless otherwise indicated.

The determination of physical and/or chemical properties of the startingcopolymers was carried out as follows:

a. Inherent viscosity, deciliters per gram, was measured at 30°C. on asolution of 0.1 g. of polymer in 100 ml. of chloroform.

b. Neutralization equivalent was determined by acid-base titration usingstandard aqueous sodium hydroxide, the anhydride being titrated asdiacid.

c. Wallace plasticity at 100°C. was determined according to thefollowing procedure:

The Wallace plasticity is a measure of the amount of flow or deformationunder load of unvulcanized elastomeric materials. The sample to betested is sheeted and cut into pellets having a thickness in the rangeof 3.18 mm to 7.6 mm (0.125 to 0.300 inch). The test is done with aWallace Plastimeter manufactured by H. W. Wallace and Co., Ltd., London.Initially, for a 15 second period, the tet pellet is compressed to athickness of exactly one millimeter and heated to 100°C. Then the testpellet is subjected to a 10-kilogram load for exactly 15 seconds at100°C. The final thickness of the test piece, expressed in units of 0.01millimeter, is the plasticity reading.

d. Melt index was measured at 190°C. under a 2160 g. load -- ASTM MethodD 1238-73, Condition E or Condition A and then converted to anequivalent value for Condition E.

The degree of polymerization (DP) or molecular weight of the starting6-nylons can be readily determined by end group analysis. The amino endgroups are determined by titration with a strong acid, either in thepresence of an indicator or by a potentiometric or a conductometricmethod. ACid end groups are determined by titration with a strong base.These techniques are discussed in Nylon Plastics, M. I. Kohan, Editor,pp. 38 and 105, John Wiley and Sons, New York (1973), and inEncyclopedia of Polymer Science and Technology, Vol. 10, pp. 542 and543, John Wiley and Sons, New York (1969).

Preparation of Trunk Copolymers (Procedures A to U)

A. prepartation of Ethylene/Methyl Acrylate/Monoethyl Maleate Copolymer

A terpolymer containing 46.4 percent ethylene, 50 percent methylacrylate, and 3.6 weight percent monoethyl maleate and displaying a meltindex of 3.6 g./10 min. was prepared in a 0.72-liter stirred autoclalve.

A mixture of methyl acrylate, monoethyl maleate, and benzene (weightratio: 68.28/2.46/29.26) was pressured to about 422 kg./sq. cm.;ethylene was separately pressured to about 422 kg./sq. cm. Separatestreams of this mixture (0.91 kg./hr.) and ethylene (6.35 kg./hr.) werejoined and pressured to 1900 kg./sq. cm. The resulting feed stream thenentered the autoclave. Simultaneously, a catalyst solution, made byadding 50 ml. of tert-butyl peroxypivalate to 4.5 kg. of benzene wasintroduced at the rate of 0.00204 kg./hr. to keep the temperature at170°C. The effluent from the autoclave passed through a let-down valveto a chamber at atmospheric pressure where most of the residual monomersand solvent flashed off. The ethylene/methyl acrylate/monoethyl maleateterpolymer thus isolated was freed from the small amount of residualvolatiles by heating for 16 hours at 80°C. in a nitrogen stream.Acid-base titration indicated that 0.25 meq. of acid groups was presentper gram of terpolymer. This corresponds to 3.6 weight percent ofmonoethyl ester of maleic acid.

B. preparation of Ethylene/Vinyl Acetate/Maleic Anhydride Copolymer

A terpolymer containing 60.3 percent ethylene, 38 weight percent vinylacetate, and 1.7 percent maleic anhydride, and displaying a melt indexof 220 g./10 min. was prepared at the rate of 0.68 kg./hr. in acontinuous 0.72-liter stirred autoclalve by the following procedure.Monomers were mixed, pressured to 1900 kg./sq. cm., and fed at theserates:

    Ethylene         4.54 kg./hr.                                                 Vinyl Acetate    2.29 kg./hr.                                                 Maleic Anhydride 0.015 kg./hr.                                            

A solution of azobis(isobutyronitrile) in benzene was simultaneouslyintroduced at a rate sufficient to keep the reactor temperature at170°C. (about 0.587 g./hr. corresponding to 0.86 kg. catalyst per 1000kg. of terpolymer). The total benzene feed was 1.04 kg./hr. Theterpolymer produced was isolated by a procedure similar to thatdescribed in Procedure A. The weight percent of maleic anhydride was1.7.

C. preparation of Ethylene/Vinyl Acetate/Maleic Anhydride Copolymer

A terpolymer containing 65.6 percent ethylene, 32 percent vinyl acetate,and 2.4 percent maleic anhydride, and displaying a melt index of 125g./10 min. was prepared at the rate of 0.63 kg./hr. in a continuous0.72-liter stirred autocalve by the following procedure. Monomers weremixed, pressured to 1900 kg./sq. cm. and fed at these rates:

    Ethylene         4.54 kg./hr.                                                 Vinyl Acetate    1.80 kg./hr.                                                 Maleic Anhydride 0.0258 kg./hr.                                           

A solution of azobis(isobutyronitrile) in benzene was introduced intothe reactor at the same time and at a rate sufficient to keep thereactor temperature at 170°C. (about 1.00 g./hr. corresponding to 1.58kg./1000 kg. of terpolymer). The total benzene feed rate was 0.67kg./hr. The terpolymer produced was isolated by a procedure similar tothat described in Procedure A. Acid-base titration with standard aqueoussodium hydroxide indicated that 0.49 meq. of diacid derived fromanhydride groups was present per gram of terpolymer. The weight percentof maleic anhydride was 2.4.

D.sub.(1) Preparation of Ethylene/Ethyl Acrylate/Allyl Acrylate/MaleicAnhydride Tetrapolymer

A 7.57-liter stirred autoclave was charged under nitrogen with 4000 ml.of methylene chloride, 400 grams of ethyl acrylate, 20 grams of maleicanhydride, 1.2 grams of allyl acrylate, and 1.0 gram ofazobis(isobutyronitrile). It was then sealed, charged with 300 grams ofboron trifluoride, and pressured to 21 kg./sq. cm. with ethylene. Thesubsequent copolymerization at 25°C. was continued until pressuremeasurement indicated that ethylene uptake had ceased (about two hourslater). The reaction was quenched by addition of 1 liter of diethylether. Volatiles were removed by steam-stripping in a well-ventilatedhood. The terpolymer thereby obtained was dissolved in acetone,precipitated in water in a blender, and oven-dried. Yield: 415 grams.

This product had about 50 mole percent ethylene units and was slightlybranched because of the use of the directive allyl acrylate. The polymerchain consisted principally of units-(E)-(B)-, where E is ethylene and Bis selected randomly from ethyl acrylate, allyl acrylate, and maleicanhydride (2.5 weight percent).

D.sub.(2) Preparation of Ethylene/Ethyl Acrylate/EthyleneDiacrylate/Maleic Anhydride Tetrapolymer

The procedure of D.sub.(1) above, was repeated except that 1.2 grams ofethylene diacrylate were used in place of the allyl acrylate. Yield: 479grams. The branched tetrapolymer obtained had about 50 mole percent ofethylene units. The polymer chain consisted principally of units-(E)-(B')-, where E is ethylene and B'is randomly selected from ethylacrylate, ethylene diacrylate, and maleic anhydride (3.8 weightpercent).

D.sub.(3) Preparation of Ethylene/Ethyl Acrylate/EthyleneDiacrylate/Maleic Anhydride Tetrapolymer

The procedure of D.sub.(1) above was repeated except that 0.75 gram ofethylene diacrylate was used in place of the allyl acrylate, and theamount of maleic anhydride was increased to 30 grams. Yield: 417 grams.The branched tetrapolymer had about 50 mole percent of ethylene units,the units being arranged -(E)-(B')-, as in D.sub.(2). The weight percentof maleic anhydride was 3.9.

D.sub.(4) Blend of Branched Alternating Copolymers

The branched copolymers made by procedures D.sub.(1), D.sub.(2), andD.sub.(3) were blended on a rubber roll mill. Table I gives theproperties of the blend and its components.

                  TABLE I                                                         ______________________________________                                                 Parts                                                                Copolymer                                                                              in                  Wallace                                                                              Neut.Eq.                                  D        Blend   Inh.Visc..sup.a                                                                           Plast. meq./g.                                   ______________________________________                                        (1)      397     1.91        16.8   0.52                                      (2)      479     1.33        15     0.77                                      (3)      417     1.21        5      0.80                                      Blend (4)                                                                              --      1.75        14     0.70.sup.b                                ______________________________________                                         .sup.a deciliters/gram; measured at 30°C. on solution of 0.1 g.        copolymer in 100 ml. of chloroform.                                           .sup.b acid-base titration using standard aqueous sodium hydroxide, the       anhydride being titrated as diacid. 3.4 weight percent of maleic              anhydride.                                                               

E. preparation of Ethylene/Ethyl Acrylate/Allyl Acrylate/MaleicAnhydride Tetrapolymer

The procedure of Part D.sub.(1) was repeated except that the pressure ofethylene was 42.2 kg./sq. cm. Yield: 233 grams. The tetrapolymer had aninherent viscosity of 2.37 deciliters/gram, a Wallace Plasticity of24.4, and a neutralization equivalent of 0.49 meq./gram. 2.4 weightpercent of maleic anhydride was present.

F.sub.(1), (2) Preparation of Ethylene/Ethyl Acrylate/AllylAcrylate/Maleic Anhydride Tetrapolymers

The procedure of Part D.sub.(1) was twice repeated except that theamount of maleic anhydride was decreased each time to 10 grams. Yields:481 grams and 497 grams. There was 1.8 weight percent of maleicanhydride in F.sub.(1) . and 2.1 weight percent of maleic anhydride inF.sub.(2) .

F.sub.(3) Preparation of Ethylene/Ethyl Acrylate/EthyleneDiacrylate/Maleic Anhydride Tetrapolymer

The procedure of Part D.sub.(1) was repeated except that 0.75 gram ofethylene diacrylate was used in place of allyl acrylate. Yield: 476grams. 2.3 weight percent of maleic anhydride was present.

F.sub.(4) Preparation of Blends of Branched Copolymers

A trunk copolymer composition was prepared by blending copolymersF.sub.(1), F.sub.(2), and F.sub.(3) on a rubber roll mill. Table IIgives characteristic properties.

                  TABLE II                                                        ______________________________________                                                 Parts                                                                         in                 Wallace                                                                              Neut.Eq.                                   Component                                                                              Blend   Inh.Visc.  Plast. meq./g.                                    ______________________________________                                        F.sub.(1)                                                                              336     1.97       15.5   0.36                                       F.sub.(2)                                                                              292     1.78       13.3   0.42                                       F.sub.(3)                                                                              241     1.52       14     0.46                                       Blend F.sub.(4)                                                                        --      1.44       13.5   0.43.sup.a                                 ______________________________________                                         .sup.a 2.1 weight percent maleic anhydride was present.                  

G. preparation of Ethyl Acrylate/Monoethyl Fumarate Copolymer

In a 3-neck round-bottom flask, a mechanically stirred mixture of 500ml. of benzene, 100 ml. of inhibited ethyl acrylate, 7.2 grams ofmonoethyl fumarate, and 0.25 gram of azobis(isobutyronitrile) was purgedwith nitrogen for 30 minutes, then heated at 50°C. under a nitrogenblanket for 24 hours. The copolymer was isolated by steam-stripping in awell-ventilated hood and dried overnight in a nitrogen-bled vacuum ovenat 70°C. Conversion was 86 percent. Prior to analysis and use, thecopolymer was purified by dissolution in acetone, precipitation in waterin a blender, and vacuum oven drying. Properties are given in Table III,below. 4.3 weight percent of mnoethyl ester of fumaric acid was present.

H.sub.(1), (2) Preparation of Ethyl Acrylate/Maleic Anhydride Copolymers

1. The reactor was a 2-liter resin flask fitted with an agitator, acondenser and a dropping funnel. A 710-ml. charge of ethyl acetate and0.2 gram of benzoyl peroxide was added and stirred under nitrogen whilebeing heated to reflux. A mixture of 500 grams of inhibitor-free ethylacrylate, 10 grams of maleic anhydride, and 1 gram of benzoyl peroxidewas placed in the dropping funnel. A 50-ml. charge of this monomer feedwas added all at once to the stirred refluxing solution in the flask;the rest was added over a period of 3.5 hours. After an additional 2hours at reflux, the reaction mixture was steam-distilled in a hood withgood ventilation to remove solvent and residual monomers. The copolymerthus isolated was washed with water on a wash mill, partially dried on ahot rubber roll mill, and then heated in a nitrogen bled vacuum oven for22 hours at 130°C. to remove residual volatiles. Yield: 448 grams.

2. The same equipment was used as in H.sub.(1) above. The ethylacrylate/maleic anhydride copolymer was prepared as follows. A mixtureof 500 grams of ethyl acrylate, 10 grams of maleic anhydride, and 0.5gram of benzoyl peroxide was added to 490 grams of refluxing ethylacetate over a 4-hour period. After about 85 percent of this feedmixture had been introduced, 140 ml. of cyclohexane and 35 ml. of ethylacetate were added. When all the feed was in, 80 ml. more of ethylacetate were added. Reflux continued for one hour. Heat was then removedand the mixture was allowed to stand for 36 hours. Finally, 0.5 gram ofhydroquinone was added and the copolymer was isolated by steam-strippingthe volatiles in a well-ventilated hood. Mill drying and vacuum ovendrying (20 hours at 130°C.) followed. Yield: 364 grams.

Properties of the copolymers prepared as described in Procedures G,H.sub.(1) and H.sub.(2) are given in Table III.

                  TABLE III                                                       ______________________________________                                                 Maleic    Inh.     Wallace Acidity.sup.b                             Copolymer                                                                              Anh.,%    Visc..sup.a                                                                            Plast.  meq./g.                                   ______________________________________                                        G        --        2.32     --      0.30                                      H.sub.(1)                                                                              1.5       1.24     5       0.31                                      H.sub.(2)                                                                              1.4       2.03     14      0.29                                      ______________________________________                                         .sup.a deciliters/gram; measured at 30°C. on a solution of 0.1 gra     of copolymer in 100 ml. of chloroform.                                        .sup.b acid-base titration with standard aqueous sodium hydroxide; values     for H.sub.(1) and H.sub.(2) were each 0.15 meq./g. when alcoholic             potassium hydroxide was used; proportion of maleic anhydride calculated       from sodium hydroxide values.                                            

I. preparation of Ethyl Acrylate/Butyl Acrylate/Monoethyl FumarateTerpolymer

The reactor was a nitrogen-blanketed two-liter resin flask fitted withan agitator, a condenser, and a dropping funnel.

Monomeric ethyl acrylate and butyl acrylate were passed through aluminato remove polymerization inhibitors. Then, 70 grams of the ethylacrylate, 70 grams of the butyl acrylate, 10.5 grams of monoethylfumarate, 21 grams of "Igepal CO-730" [nonylphenoxy - poly(ethyleneglycol) having about 15 --O--CH₂ --CH₂ -- units], 1050 grams of water,and 1.0 gram of ammonium persulfate were added to the resin flask andheated to reflux. A mixture of 113 grams of ethyl acrylate, 113 grams ofbutyl acrylate, 9.4 grams of monoethyl fumarate, and 3.8 grams of IgepalCO-730 was gradually introduced at a rate to keep the reactiontemperature at 89° to 93°C. after 1.4 hours, all the feed had been addedand stirring was becoming difficult. After an additional 20 minutes, thetemperature of the reaction mixture had risen to 96°C., whereupon 0.15gram of hydroquinone was added, and residual monomers were removed by a2-hour steam-distillation in a well-ventilated hood.

Coagulated polymer was washed by chopping in a blender with water, twicedissolved in acetone and reprecipitated in water in a blender, thenair-dried, vacuum-oven dried 3.5 hrs. at 72√C., and finally mill-driedat about 130°C. Yield: 254 g. The terpolymer produced had an inherentviscosity (chloroform, 30°C.) of 1.51 deciliters/gram and an acidcontent of 0.24 meq./gram (titration with aqueous sodium hydroxide), or0.23 meq./gram (titration with alcoholic potassium hydroxide). Theterpolymer had 3.3 percent monoethyl fumarate; the remainder wasbelieved to be about equally divided between ethyl acrylate and butylacrylate.

J. epdm/maleic Anhydride Adduct

Maleic anhydride was grafted on an ethylene/propylene/1,4-hexadienecopolymer. The ethylene/propylene/1,4-hexadiene copolymer was asulfur-curable elastomer having a Mooney (ML-1 +4/121°C.) viscosity ofabout 35 and the following monomer unit composition: ethylene, 61.4weight percent; propylene, 32 weight percent; 1,4-hexadiene, 6.6 weightpercent. The copolymer had about 0.5 gram mole of ethylenicallyunsaturated side chains per kilogram. Its Wallace Plasticity was about28 at 100°C. and its inherent viscosity was about 2.0 (measured at 30°C.on a solution of 0.1 gram of copolymer in 100 milliliters oftetrachloroethylene). Copolymerization was carried out in solution inhexane in the presence of a Ziegler catalyst forming by mixing VCl₄ anddiisobutylaluminum chloride.

A Werner and Pfleiderer 53 mm twin screw extruder was assembled byend-to-end attachment of sixteen barrel sections of 1.27 cm. diameter.Following a short feed section were four reaction sections (zones 1-4),one vacuum port section (zone 5), a cooling section (zone 6), and a diesection. Provisions were made for the metering of molten maleicanhydride at the forward part of zone 1. The screws were composed ofkneading blocks, reverse pitch screws, and transport screws arranged togenerate 7.0-14.1 kg./sq. cm. pressure in zones 1-4 and no pressure inzone 5. The free volume of zones 1-5 was equivalent to 0.91 kg. ofpolymer at operating temperature. Zones 1-4 were preheated to 300°C.,zone 5 to 260°C., and zone 6, the cross-head, and the die to 150°C.

The above ethylene/propylene/1,4-hexadiene copolymer was fed to theextruder in the form of chips which passed a 1.27 cm. screen. Maleicanhydride was metered to the extruder at an average feed rate of 4.8percent of the polymer weight. The screw speed was 12 rpm, and thevacuum port was operated at about 63.5 cm. of Hg.

The product, extruded at the rate of 2.79 kg./hr., had a maleicanhydride content of 2.23 percent, as determined by infraredspectroscopy, and 2.19 percent by weight as determined by titration intetrahydrofuran with 0.1 M tetrabutylammonium hydroxide in methanol.Wallace plasticity of the product was 33, and gel content was less thanabout 5 percent.

Following purification of a small sample by solution in tetrahydrofuranand precipitation with anhydrous acetone, the maleic anhydride contentwas 2.19 percent and 2.05 percent by weight, respectively, by infraredand titration determination. The gel content was less than about 5percent. The inherent viscosity was 1.5 deciliters/gram as measured on0.1 gram of adduct dissolved in 100 milliliters of perchloroethylene at30°C.

The rest of the product was washed on a wash mill at 125°C. for 20minutes and dried on a 15.2 × 30.5 cm. mill.

A series of additional ethylene trunk copolymers (Procedures K to Vlisted in Table IV) were prepared containing maleic anhydride as onecomonomer by a copolymerization reaction described above.

                                      TABLE IV                                    __________________________________________________________________________                         Comonomer                                                Procedure                                                                            Ethylene Copolymer                                                                           Ratio   Melt Index                                      __________________________________________________________________________    K     Ethylene/Vinyl Acetate/                                                                      78.4/20.1/1.5                                                                          12                                                    Maleic Anhydride                                                        L     "              "        12                                              M     "              73.8/24.6/1.6                                                                          26                                              N     Ethylene/Maleic Anhydride                                                                    96/4     15                                              O     "              87.7/12.3                                                                              750                                             P     Ethylene/Vinyl Acetate/                                                                      74/24/1.8                                                                              220                                                   Maleic Anhydride                                                        Q     Ethylene/3-Methylbutene/                                                                     10.8% Maleic                                                                           1700                                                  Maleic Anhydride                                                                             Anhydride                                                R     "              21% Maleic                                                                             2000                                                                 Anhydride                                                S     Ethylene/Vinyl Acetate/                                                                      71/20/8.5                                                                              920                                                   Maleic Anhydride                                                        T     Ethylene/Maleic Anhydride                                                                    88/12    750                                             U     Ethylene/Vinyl Acetate/                                                                      60/38/1.7                                                                              220                                                   Maleic Anhydride                                                        V     "              62/33/4.8                                                                              290                                             __________________________________________________________________________

Preparation of Side Chain Polymers (amine terminated) Procedure AA

A heavy glass tube was used to prepare a low molecular weight polymer.Into the tube was placed 50 g. of caprolactam, 10 ml. of n-hexyl amine,0.25 ml. of water. The tube was flushed with nitrogen and sealed offunder vacuum. The tube was heated to 220°C. for 151/2 hours.

The polymer was removed from the tube and washed with hot water toremove residual unreacted caprolactam and amine and dried. The polymerwass found to have a melting point of 165°C. by Differential ThermalAnalysis (DTA). Analysis of end groups showed 940 milli-equivalents/Kg.of NH₂. These results were calculated to give a molecular weight ofapproximately 1050.

Procedure BB

In a procedure similar to that in Procedure AA, a polyamide wasprepared. Components were 50 g. of caprolactam and 12.5 ml. of n-hexylamine. The tube was heated to 255°C. for 20 hours. The polyamide had amelting point of 177°C.

Procedures CC to GG

A heavy stainless steel tube was used to prepare low molecular weightpolyamide polymers. N-hexyl amine was used as the chain initiator in theamounts used as listed in Table V. Solid, normal standard purificationcaprolactam was used. This probably contained trace amounts of water.Otherwise water was excluded from the reaction to prevent initiation bywater and subsequent termination of chains by carboxyl groups. The tubewas evacuated and flushed with nitrogen to prevent oxidative reactionsand then refilled with nitrogen before sealing and heating. The tube wasagitated during the reaction period. In all procedures the tube washeated to 255°C. during this period.

The analysis of the product was in terms of melting point andend-groups. The end-group analysis showed that only about 0.2 percent ofthe molecules were terminated by carboxyl groups.

                                      TABLE V                                     __________________________________________________________________________                     N-Hexyl      DTA                                                   Caprolactam                                                                          H.sub.2 O                                                                         Amine Temp.                                                                             Time                                                                             MP  Milliequivalents/Kg                                                                       Mol.                            Procedure                                                                           g.     Ml  Ml    °C.                                                                        Hrs.                                                                             °C.                                                                        NH.sub.2                                                                            COOH  Wt.                             __________________________________________________________________________    CC    50     0   9     255 16 187  943  1.7   1050                            DD    50     0   10.5  255 16 193  871  2.6   1140                            EE    50     0   11.5  255 16 196  877  1.7   1130                            FF    50     0   10.5  255 16 193 1171  1.3    847                            GG    150    0   31.5  255 16 191 1027  1.6    960                            __________________________________________________________________________

Procedures HH to OO

In a manner similar to Procedures CC to GG polyamides were made as shownin Table VI. Reaction conditions were 255°C. for about 16 hours.

                                      TABLE VI                                    __________________________________________________________________________                               DTA MP                                                                             Milliequivalents/Kg                                                                         Molecular                       Procedure                                                                            Lactam     Amine    °C.                                                                         NH.sub.3                                                                          COOH      Weight                          __________________________________________________________________________    HH     50g. caprolactam                                                                         20 g. stearyl                                                                          204   934                                                                              None detectable                                                                         1062                                               amine                                                      II     "           5 g. butyl                                                                            204   825                                                                              "         1208                                               amine                                                      JJ     50g. laurolactam                                                                         10.5 ml n-                                                                             200   492                                                                              "         >1800                                             hexylamine                                                  KK     47.5g. caprolactam                                                                       "        189  1169                                                                              "         847                                     2.5g. laurolactam                                                     LL     45g. caprolactam                                                                         "        184  1113                                                                              8.4       892                                     5g. laurolactam                                                       MM     40g. caprolactam                                                                         "        177  1103                                                                              None detectable                                                                         903                                    10g. laurolactam                                                       NN     80g. caprolactam                                                                         12 ml. n-                                                                              180   720                                                                              1.6       1390                                   25g. laurolactam                                                                         hexylamine                                                  OO     70g. caprolactam                                                                         4 ml. n-hexyl-                                                                         173   345                                                                              8.0       >1800                                  30g. laurolactam                                                                         amine                                                       __________________________________________________________________________

Procedures PP to XX

Amine-terminated polyamides were prepared by procedures PP-XX which arecompletely summarized in Table VII below. Additional details areprovided for Procedures QQ, SS, VV and XX which are typical processes.

Procedure QQ

In each of two 400 ml. stainless steel rocker bombs was placed a mixtureof 120 g. of caprolactam, 10 g. of stearyl-amine, 0.3 g. of diethylphosphate, and 120 ml. of benzene. Both bombs were flushed withnitrogen, sealed under nitrogen, and shaken at 275°C. for 17 hours. Thebenzene-wet cakes of granular product were combined and soaked inacetone for 5 days, then extracted overnight with acetone in a Soxhletassembly. The resulting powdery amine-terminated nylon product wasair-dried in a hood, then vacuum-over dried at 50°C. for 1 hour.Analyses are in Table VII.

Procedure SS

A charge of 300 g. of caprolactam and 100 ml. of water was sealed undernitrogen in a 1.4-liter stainless steel rocker bomb and heated over aperiod of 2.1 hours to 280°C., held there for 3 hours, then cooled toroom temperature. After an additional 650 ml. of water had been addedunder nitrogen, the bomb was again sealed and shaken while beingsubjected to the following temperature schedule: 1.2 hours heating toreach 210°C, 15 minutes at 210°C., cooling over 20 minutes to 135°C., 2hours at 135°C., then cooling over 1.2 hours to room temperature. Theresulting product, a partial slurry of powder, granules, and cake, waspartly de-watered by filtration, then chopped in a blender with freshwarm water. Acetone was added to increase slurry volume by 50 percent,and the solids were isolated by filtration. After being air-dried in ahood, then dried in a vacuum oven for 8 filled with at 100°C. (nitrogenbleed), the amine-terminated nylon product weighed 217 grams. Analysesare in Table VII.

Procedure VV

A charge of 769 grams of caprolactam, 32 grams of butylamine, and 15grams of water was sealed under nitrogen in a 1.4-liter stainless steelrocker bomb, heated over a 2.5-hour period to 280°C., shaken at 280°C.for 7 hours, then cooled over a 3.21hour period to room temperature. Theproduct, a brittle cake, was mechanically chopped to a coarse granularcondition. A 317.9-gram portion of the total product was rolledovernight in a sealed 7.57-liter jar with 1.42 liters of methanol.Insoluble material was collected on a filter, washed in two portionswith 0.47 liter of methanol, briefly air-dried, and then dried in anitrogen-bled vacuum oven for 3 hours at 75°C. Dry extracted productweighed 267.6 grams. Analyses of a smaller sample (15 grams) similarlyextracted with methanol are shown in Table VII.

Procedure XX

A mixture of 70 grams of caprolactam, 6 grams of 1-octadecylamine, and195 milliliters of diphenyl ether was placed in a 0.4 liter stainlesssteel rocker bomb. After the system had been evacuated and filledwithnitrogen two times, it was closed under vacuum and shaken for about 8hours at 260°C.; heating and shaking continued for 2 days, the finaltemperature being 235°C.

The resulting mixture was washed on a filter with acetone and shaken forthree days in acetone to remove diphenyl ehter. The product wascollected on a filter, washed with acetone, and extracted overnight in aSoxhlet extractor with acetone. Drying in air and then a vacuumdesiccator at 50°C. gave the 6-nylon as a powder having an inherentviscosity of 0.21 deciliters/gram (at 30°C. in m-cresol) and 0.383,0.388 eq. --NH 2 groups/kg. (corresponding to a molecular weight ofabout 2600 and a DP of about 21).

                                      TABLE VII                                   __________________________________________________________________________    Low Molecular Weight Amine-Terminated 6-Nylon Preparations                    Nitrogen-Blanketed Polymerization                                                                PP  QQ  RR   SS   TT   UU   VV   WW   XX                   Charge Composition, G.                                                        __________________________________________________________________________    Caprolactam        140 240 295  300  283  283  769  769  70                   Stearylamine       10  20                                6                    Octylamine                 23        32.2 20.8                                Butylamine                                     32   32                        ε-aminocaproic acid                                                                              5                                                  Water                           100  4    4    15   15                        Diethyl phosphate  0.2 0.6                                                    Diphenyl ether     135                                   195                  Benzene                240                                                    Post-polymerization Diluent, g..sup.a                                         Benzene                    300                                                Water                           650                                           Methanol                             451  451                                 Polymerization Conditions                                                     Hastelloy or stainless steel                                                   rocker tube vessel size, 1.                                                                     0.4 2 × 0.4                                                                     1    1.4  1.4  1.4  1.4  1.4  0.4                  Reaction temperature, °C..sup.b                                                           260 275 245, 230                                                                           280, 210                                                                           280, 230                                                                           280, 230                                                                           280  245  260, 235             Reaction time, hrs..sup.b                                                                        19.5                                                                              17  20, .5                                                                             3, .3                                                                              3.5, .5                                                                            3.5, .5                                                                            7    3    56                   Granulation Technique.sup.a                                                                      diluent                                                                           diluent                                                                           diluent                                                                            diluent                                                                            diluent                                                                            diluent                                                                            chopping                                                                           chopping                                                                           diluent              Purification Technique                                                        Overnight Soxhlet extraction                                                   solvent           ace-                                                                              ace-                              acetone              Overnight reflux in 10X wt.                                                                      tone                                                                              tone                                                    solvent                   water                                              Overnight roller extraction,                   methanol                        solvent                                                                      Blender washing, solvent        g    h                                        Centrifugation/decantation                                                     washing, solvent (reps.)                 meth-                               After filtration collection,              anol.sup.3                           air drying:                                                                   Vacuum oven (N.sub.2 -bleed) drying:                                          Temp./Time(°C./hrs.)                                                                         50/1                                                                              100/40                                                                             100/8                                                                              100/15                                                                             100/24                                                                             75/3                           Purified 6-Nylon Properties                                                   Yield, g.          101.5                                                                             ˜180                                                                        ˜258                                                                         217  250  222.2                                                                              ˜652                                                                         798.3                     NH.sub.2 end-groups, meq./g..sup.c                                                               0.198                                                                             0.241                                                                             0.428                                                                              0.45 0.61 0.46 ˜0.46                                                                        0.495.sup.f                                                                        0.383                COOH end-groups, meq./g..sup.d                                                τ inh (m-cresol, °30 C.)                                                              0.38                                                                              0.36                                                                              0.27 0.30 0.19 0.23 ˜0.29                                                                             0.21                 DSC melting point, °C..sup.e                                                              216 217 210  220  209.5                                                                              214  ˜217                     Molecular weight from NH.sub.2                                                 titration         5050                                                                              4150                                                                              2336 2220 1640 2170 2170 2020 2600                 DP                 42.4                                                                              34.5                                                                              19.5 19.5 13.5 18   18.5 17   21                   __________________________________________________________________________    FOOTNOTES FOR TABLE VII                                                        .sup.a Inert diluent provided the nylon in finely-divided form if the         polymerizate was shaken with the diluent above the melting point of the       nylon.                                                                        .sup.b The Table does not include times requied to reach reaction             temperature (usually 1.3-2.3 hours) or cool down (˜1-3 hours). A        second pair of temperature and time values refers to a second heating         period after addition of post-polymerization diluent.                         .sup.c A˜0.8-gram nylon sample is dissolved by warming in 25 ml. of     o-cresol, and treated with 1.5 ml. of water, than 7.5 ml. of chloroform,      cooled, and titrated potentiometrically (Beckmann No. 39501 combination       electrode) with standard 0.03N ethanolic potassium hydroxide.                 .sup.d A˜0.1 gram nylon sample is dissolved by warming in 80-ml.        m-cresol. After cooling, 10 ml. of chloroform is added and the resulting      composition is titrated potentiometrically (glass-modified calomel            electrode) with standard 0.01N 2,4-dinitrobenzenesulfonic acid in acetic      acid.                                                                         .sup.e Samples were programmed at 10°C./min. through a cycle of        50°C.→250°C.→50°C.→250°C    , and the peak melting endotherm of the second heating cycle taken as the      melting point. A shoulder at a lower temperature was usually observed.        .sup.f Caprolactam, residual amine initiator, and low oligomers had not       been extracted before analysis.                                               .sup.g Blender washing, solvent, SS: (1) hot H.sub.2 O, (2) acetone/H         .sup.h Blender washing, solvent, TT: (1) methanol, (2) methanol/acetone       (5/2).                                                                   

Procedures YY to KKK Procedure YY

Caprolactam/n-Hexylamine Oligomer

A 200-ml. pressure reactor was charged with 50 g. (0.442 mole) ofε-caprolactam (CL), 10 g. (0.099 mole) of n-hexylamine (HA) and 0.2 g.(0.011 mole) of water. The reactor was cooled in a dry ice-acetone bath,evacuatively purged twice with nitrogen, evacuated, and heated at 250°C.for 16 hours with the contents under autogenous pressure. The cooledproduct was a soft white solid. A 45-g. portion was extracted bycentrifugation first with about 900 ml. of 1:1 acetone:water andsecondly with acetone. The air-dried residue weighed 25.5 g., and couldbe readily crushed to a fine powder. Analysis showed 865 equivalents ofamino end groups per 10⁶ g., corresponding to a degree of polymerization(DP) of about 9. Differential scanning calorimetry (DSC) showed a majormelting endotherm at 196°-198°C.

The above procedure, except that water was omitted, was used to prepareadditional samples of CL/alkyl-amine oligomers. Reactors up to 1300-mlsize were used as appropriate. The data for these preparations arepresented in the following Table VIII.

                                      TABLE VIII                                  __________________________________________________________________________    Caprolactam/n-Alkylamine Oligomers                                                                   DSC   End Groups                                              CL  Amine Yield.sup.a                                                                         mp    (eq/10.sup.6 g)                                                                         DP                                     Procedure                                                                            (g) (g)   (g)   (°C)                                                                         NH.sub.2                                                                           CO.sub.2 H                                                                         (Approx.)                              __________________________________________________________________________     ZZ.sup.b                                                                             50 HA, 5 20.8  205   710  54   12                                     AAA    100 HA, 20                                                                              83.2  184   1162 5.8  7                                      BBB     50 HA, 2.5                                                                             31.0   207-8                                                                              590  8.84 15                                     CCC    100 HA, 20                                                                              78.0  --    (1160)                                                                             --   7                                      DDD     50 HA, 5 38.0  --    785  27.6 10                                     EEE     50 HA, 1.5                                                                             27.0  --    442  10.2 20                                     FFF    100 HA, 20                                                                              71.2  --    (1160)                                                                             --   7                                      GGG    100 HA, 29                                                                              47.0  177   1322 0.4  5.8                                    HHH    600 HA, 120                                                                             529.5 --    1189 4.3  6.5                                    III     50 HA, 53                                                                              24.3.sup.d                                                                          --    2285 --   3                                      JJJ    200 BA.sup.c,29                                                                         171   --    1237 --   6.5                                    KKK    100 ODA.sup.c,54                                                                        108   --    1076 --   5.8                                    __________________________________________________________________________     .sup.a All runs with acetone as primary extraction solvent.                   .sup.b Reaction mixture also contained 50 ml. benzene and 0.2 g. diethyl      phosphate; reaction run at 275°C.                                      .sup.c BA = n-butylamine; ODA = n-octadecylamine.                             .sup.d Extracted with petroleum ether, benzene and diethyl ether.        

Procedures LLL to NNN

Laurolactam/n-Hexylamine Oligomers

Following Procedure YY, except that a temperature of 300°C. was used,laurolactam/n-hexylamine (LL/HA) oligomers were prepared fromlaurolactam (cyclic lactam from 12-aminolauric acid) and n-hexylamine.The data are presented in the following Table IX.

                                      TABLE IX                                    __________________________________________________________________________    Laurolactam/n-Hexylamine Oligomers                                                               DSC End Groups                                             LL.sup.a  HA  Yield                                                                              mp  (eq /10.sup.6 g)                                                                      DP                                             Procedure                                                                           (g) (g) (g)  (°C)                                                                       NH.sub.2                                                                          CO.sub.2 H                                                                        (Approx.)                                      __________________________________________________________________________    LLL.sup.d                                                                           100 50  48.5.sup.b                                                                         --  1335                                                                              --  3.3                                            MMM    50  7.5                                                                              35.5.sup.c                                                                         162  733                                                                              --  6.5                                            NNN    50  5.0                                                                              31.8.sup.c                                                                         164  657                                                                              --  7.2                                            __________________________________________________________________________     .sup.a All runs with 0.4% water, based on laurolactam.                        .sup.b Acetone used as primary extraction solvent.                            .sup.c Methanol used as primary extraction solvent.                           .sup.d Run in 400-ml reactor.                                            

Procedures OOO to PPP

Preparation of NH₂ -Terminated 12-Nylons

Procedure OOO

A mixture of 59.6 grams of ω-alurolactam and 4.8 grams of1-octadecylamine was heated in a glass polymer tube. After the resultingmelt had been allowed to crystallize, 0.16 gram of diethyl phosphate(CH₃ CH₂ O)₂ PO₂ H was added. The tube was then evacuated and filledwith nitrogen about five times. While under vacuum the neck of the tubewas sealed. The mixture was then heated at about 285° to 288°C. forabout 9.5 hours. The 12-nylon obtained (yield about 45 grams) had amelting point of about 145°-150°C., an inherent viscosity of 0.34 (at30°C. in m-cresol), and 0.225, 0.226 equivalent of --NH₂ groups perkilogram (corresponding to a molecular weight of 4430 and a DP of about21).

Procedure PPP

A mixture of 50 grams of ω-laurolactam and 10.5 ml. (13.8 g.) ofn-hexylamine was placed in a heavy stainless steel tube, which wasevacuated, flushed with nitrogen, and filled with nitrogen, then sealedand heated 16 hours at 255°C. The resulting nylon contained 0.492equivalent of --NH₂ groups per kilogram. The molecular weight of thenylon thus was about 2030 and its DP was about 9.5.

Additional 12-Nylons

Additional 12-nylons were made by method PPP using n-hexylamine as thepolymerization initiator. The products had DP's of 5.3, 7.0, 10.2, 14.3,15.6, 24.0, and 15.6, respectively.

EXAMPLES 1-13

The following tests were used in the Examples to provide propertymeasurements of the graft copolymers.

The Izod Impact Strength test (Izod) was determined by standard ASTM D256-73. Samples are compression molded in a lab press at 190°C. in theform of 76 mm × 76 mm × 3.18 mm sheets. Bars 63.5 mm × 12.7 mm are cutfrom the sheet and notched as specified in ASTM D 256-73. Samples areallowed to condition at room temperature for 16-24 hous, after cuttingand notching, before testing. Five bars of each sample are tested andthe average value reported as the Izod Impact Strength in kg.-cm./cm. ofnotch.

Variable Height Impact was determined by compression molding sheets in apress at 190°C. to a thickness of 0.76-1.02 mm. These are allowed tocondition at room temperature for 16-24 hours before testing . The testis run using a Gardner Impact Tester, Model IG-1120M. The tester has a3.63 kilogram weight with a 12.7 mm diameter ball end. It is droppedonto a sample supported on a metal plate having a 16.3 mm diameter holedirectly under the impact point of the weight. The weight falls througha tube which is marked in kg.-cm. The point at which the weight isreleased is recorded as the impact energy for that drop. The force atwhich 50 percent of the samples break is reported as the Gardner ImpactStrength in kg.-cm. The samples may be measured as to thickness and thevalues reported as impact strength in kg.-cm./ mm.

Vapor Pressure Osmometry was determined by a standard method describedin R. U. Bonnar, M. Dimbat and F. H. Stross, Number-Average MolecularWeights, Interscience, N.Y., 1958. This is a solution method; thesolvent must be a good solvent for the material being evaluated. Apreferred solvent was o-dichlorobenzene, and the test temperature was100°C.

Flexural Modulus was measured by standard ASTM D-790-71 or as modified.Samples are compression molded at 190°C. in a laboratory press in theform of 127 mm × 12.7 mm × 3.18 mm bars (or 50.8 mm × 12.7 mm film). Thebars (film) are conditioned at room temperature 16-24 hours beforetesting. The test is conducted using a 50.8 mm (or 25.4 mm) span at acrosshead speed of 1.27 mm/min. (or 5.1 mm/min.). The tangent modulus ofelasticity (flexural modulus) is calculated using the equation given inthe ASTM procedure. The value obtained is expressed in flex modulus inkg./sq. cm.

Heat Deflection Temperature was determined by compression moldingsamples in a laboratory press at 190°C. in the form of 127 mm × 12.7 mm× 3.18 mm bars. These bars are tested in accordance with the procedurestated in ASTM D 648. The bars are allowed to condition at roomtemperature for 16-24 hours before testing. Weights are placed on theloading rod to obtain a fiber stress of 18.56 kg./sq. cm. and the barsare heated in a bath until a deflection of 0.25 mm is measured. Thetemperature at which the bar is deflected 0.25 mm is reported as thedeflection temperature at 18.56 kg./sq. cm. fiber stress.

Preparation of Graft Copolymers

Table X below summarizes the preparation, composition, and properties ofrepresentative graft copolymers of the present invention.

For all graft products, slabs for testing could be prepared by briefcompression molding at 235°C., followed by rapid (˜2 min.) cooling andimmediate demolding. Annealing of these slabs at 135°C. for 4 to 5 hoursgenerally improved compression set about 20 to 35 points but had littleeffect on other properties. The grafting procedure used in Example 7 ofTable X is illustrative of the process:

A mixture of 36 grams of the ethylene/vinyl acetate/maleic anhydridetrunk copolymer of Procedure C, 14 grams of the powdered low molecularweight, H₂ N-terminated 6-nylon of Procedure SS, 0.1 gram oftris(mono-and di-nonylphenyl) phosphite stabilizer ["Polygard" fromUniroyal], 0.1 gram of stabilizerN-phenyl-N'-(p-toluenesulfonyl)-p-phenylene-diamine ["Aranox" fromUniroyal], 0.1 gram of1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene["Ionol 330" from Shell], and 0.05 gram of a 7:1 weight mixture ofpotassium iodide and cuprous iodide was homogenized as thoroughly aspossible on an unheated rubber roll mill. The resulting blend was thentransferred to an electrically heated mill held at 215°C. and masticatedat 215°C. under a partial nitrogen blanket for 15 minutes to effectgrafting. At this point the material was ready for fabrication.

                                      TABLE X                                     __________________________________________________________________________    Graft Copolymer Preparation, Composition, and Properties                      Example  1    2   3   4.sup.a                                                                           5   6     7  8   9   10  11  12  13                 __________________________________________________________________________    Trunk                                                                         Copolymer                                                                              E    F.sub.(4)                                                                         D.sub.(4)                                                                         F.sub.(1)                                                                         H.sub.(2)                                                                         H.sub.(1)                                                                           C  B   A   A   G.sup.c                                                                           I.sup.c                                                                           I                  "type.sup.b                                                                            Branched                                                                           Blend                                                                             as in                                                                             as in                                                                             EA/MAnh                                                                           as in E/ as in                                                                             E/MA/                                                                             as in                                                                             EA/ EA/BA/                                                                            as in                       Alt. E/                                                                            Bran-                                                                             Ex. 2                                                                             Ex. 1   Ex. 5 VAc/                                                                             Ex. 7                                                                             MAME                                                                              Ex. 9                                                                             FAME                                                                              FAME                                                                              Ex. 12                      EA/AA/                                                                             ched                  MAnh                                               MAnh Alt. E/                                                                       EA/MAnh                                                         "graft site                                                                            MAnh as in                                                                             as in                                                                             as in                                                                             as in                                                                             as in as in                                                                            as in                                                                             MAME                                                                              as in                                                                             FAME                                                                              as                                                                                as in                            Ex. 1                                                                             Ex. 1                                                                             Ex. 1                                                                             Ex. 1                                                                             Ex. 1 Ex. 1                                                                            Ex. 1   Ex. 9   Ex.                                                                               Ex. 11             "graft site conc.                                                             meq./g.  .235 .215                                                                              .35 .18 .15 .155  .245                                                                             .173                                                                              .25 .25 .29 .24 .24                Side chain                                                                    polymer  UU   VV  WW  PP  QQ  SS    TT RR  TT  TT  TT  TT  TT                 "initiator.sup.d                                                                       Octyl-                                                                             Butyl-                                                                            as in                                                                             Stearyl                                                                           as in                                                                             H.sub.2 O                                                                           as in                                                                            as in                                                                             as in                                                                             as in                                                                             as in                                                                             as                                                                                as in                       amine                                                                              amine                                                                             Ex. 2                                                                             NH.sub.2                                                                          Ex. 4     Ex. 1                                                                            Ex. 1                                                                             Ex. 1                                                                             Ex. 1                                                                             Ex. 1                                                                             Ex.                                                                               Ex. 1              "NH.sub.2 conc.                                                               meq./g.  .46  ˜.46                                                                        ˜.495                                                                       .198                                                                              .24 .45   .61                                                                              .428                                                                              .61 .61 .61 .61 .61                phr Nylon.sup.e                                                                        50.6 40  50  80  55  30    39 34  40  39  50  39  39                 Graft Reaction                                                                         Extruder                                                                           Plasto-                                                                           Plasto-                                                                           Plasto-                                                                           Plasto-                                                                           Mill.sup.g                                                                          Mill                                                                             Plasto-                                                                           Extrud-                                                                           Mill                                                                              Mill                                                                              Mill                                                                              Plasto-            Apparatus     graph.sup.f                                                                       graph                                                                             graph                                                                             graph        graph                                                                             er              graph              Graft Reaction                                                                Conditions:                                                                   Reactor Wall                                                                  Temp. °C.sup.n                                                                  ˜230                                                                         220 220 ˜210.sup.i                                                                  ˜210.sup.i                                                                  220   215                                                                              220 ˜230                                                                        215 210 210 220                Residence Time,                                                               min.     ˜16.4                                                                        10  10  20  20  15    15 18  ˜6.7                                                                        15  12  12  10                 Graft Copolymer                                                               Physical                                                                      Properties.sup.j                                                              Shore A Hardness                                                                       83   76  81  85  77  64    91 85  67  63  92  83  71                 T.sub.B, Kg./cm..sup.2                                                                 224  220 165 189 159 120   167                                                                              162 141 134 139 97  87.9               E.sub.B, %                                                                             370  460 430 300 220 270   390                                                                              330 480 500 180 210 240                M.sub.100, Kg./cm..sup.2                                                               85.8 67  58  110 79.4                                                                              58    78.4                                                                             84  48  28  115 70  34                 Comp. Set (22                                                                 hrs./70°C.,                                                            Method B), %                                                                           23   22  35  33  26  35    32 34  28  34  37  38  43                 __________________________________________________________________________    FOOTNOTES FOR TABLE X                                                          .sup.a A small amount (0.4 phr) of aniline was added after the grafting       reaction.                                                                     .sup.b E = ethylene; EA = ethyl acrylate; (alt.) refers to alternating,       rather than random copolymer, VAc = vinyl acetate; MA = methyl acrylate;      BA = butyl acrylate; AA = allyl acrylate; MAnh = maleic anhydride; MAME =     monoethyl maleate; FAME = monoethyl fumarate. These units are                 copolymerized in the trunk copolymer.                                         .sup.c Mill blends were treated 15 hours in a nitrogen-bled 130°C.     vacuum oven just before the grafting reaction. Subsequent experiments         showed that this treatment had negligible effect on product physical          properties.                                                                   .sup.d The alkyl group of the initiator becomes one end-group of nearly       all the polymer chains. The other end-group is nearly always NH.sub.2.        .sup.e Parts of nylon by weight per hundred parts of trunk copolymer.         .sup.f Brabender Plastograph, an apparatus having a small, electrically       heated chamber with two convoluted rollers capable of shear-mixing and        masticating polymer at a selected high temperature.                           .sup.g An electrically-heated mill was used for the required temperature.     .sup.h Polymer is not necessarily at this temperature at all times. There     is usually an initial warm-up period followed by a modest overshoot,          perhaps because of an exothermic reaction.                                    .sup.i Accurate temperature readings were not obtained here.                  .sup.j All graft products, in addition to the components listed here,         contained a mixture of stabilizers quite similar to that described in the     detailed Example (7). The following ASTM methods were used: Shore A,          D-2240-68; Tensile Stress (T.sub.B), D-412-68; Tensile Strain (E.sub.B),      D-412-68; Stress at 100% Elongation (M.sub.100), D-412-68; (all values        measured at 25°C.). Compression Set after 22 hours at 70°C.     D-395-67. Specimens were annealed for 4 hours at 135°C.           

EXAMPLES 14-22 Preparation of Additional 6-Nylon and of 12-Nylon GraftCopolymers Based on Ethylene/Methyl Acrylate/Monoethyl MaleateCopolymers

Copolymers of ethylene, maleic anhydride (MA), and monoethyl maleate(MAME) were prepared according to the method A, above, except that theproportions of the comonomers were varied. Grafting of low molecularweight 6-nylons and 12-nylons was accomplished either on a roll millunder nitrogen blanket at about 225°C. or in a twin screw extruder atabout 225°C. Detailed information on these preparations is presented inTable XI, below.

For testing for tenstile strength and flexural modulus the specimenswere injection molded at 225°-235°C. and held under nitrogen for atleast one day at 23°C. The following test procedures were used:

For tensile strength and elongation at break ASTM D-638-72. For flexuralmodulus D 790-71. Torsion modulus values were measued in the mannerdescribed in Anelastic and Dielectric Effects In Polymeric Solids by N.G. McCrum, B. E. Read and G. Williams, pps. 192-195, Johwn Wiley andSons, Inc., New York (1967). For melt index standard test ASTMD-1238-73, Condition E or Condition A and then converted to anequivalent value for Condition E.

                                      TABLE XI                                    __________________________________________________________________________    Example           14   15   16   17   18   19   20   21   22                  __________________________________________________________________________    Trunk Polymer                                                                 % Ethylene        36.3 36.3 40.6 40.6 42.8 42.8 42.8 42.8 40.8                % Methyl Acrylate 39.7 39.7 50.8 50.8 51.4 51.4 51.4 51.4 50.8                % MAME            24   24   8.64 8.64 5.76 5.76 5.76 5.76 8.84                Melt Index        32.8 32.8 6.6  6.6  4.5  4.5  4.5  4.5  6.6                 Nylon             6    6    6    6    6    6    12   6    12                  DP                7.0  7.0  10.2 14.3 24.0 24.0 15.6 39.5 5.3                 End Group         H.A..sup.a                                                                         H.A..sup.a                                                                         COOH COOH COOH COOH H.A..sup.a                                                                         COOH H.A..sup.a          % Polyamide       25   35   25   33   25   35   25   40   25                  Reaction Type     Roll Mill                                                                          Roll Mill                                                                          Roll Mill                                                                          Roll Mill                                                                          Roll Mill                                                                          Roll Mill                                                                          Roll Mill                                                                          Extruder                                                                           Extruder            Equiv. Ratio,     2.23 1.38 1.05 1.00 1.63 1.02 1.90 1.34 1.04                1/2 MAME/NH.sub.2                                                             DTA Melt. Pt., °C.                                                     Peak              158, 165                                                                           180  207  209  214  212  168  208  158                 End               220, 231                                                                           195  213  213  219  219  175  217  163                 Flex. Modulus, kg./cm..sup.2                                                                    552  1083 91   178  132  23   30   1019 510                 Tensile Strength, kg./cm..sup.2                                                                 61   92   68   62   61   25   44   145  98                  Elongation at break, %                                                                          190  130  400  230  120  300  620  310  190                 Torsion  Modulus × 10.sup.-.sup.9, dynes/cm..sup.2                      -180°C     12.66                                                                              14.77                                                                              14.90                                                                              16.19                                                                              15.54                                                                              15.29                                                                              27.59                                                                              14.41                                                                              14.69               -100°C.    9.80 11.94                                                                              10.18                                                                              11.84                                                                              11.07                                                                              9.23 16.97                                                                              9.59 8.96                -50°C.     7.41 8.42 4.76 6.65 5.42 5.60 9.39 5.54 6.20                0°C.       1.57 2.13 .07  .20  .18  .06  .10  1.00 .22                 20°C.      .90  1.64 .05  .16  .16  .04  .10  .89  .18                 50°C.      .28  .60  .04  .11  .12  .03  .08  .65  .12                 100°C.     .09  .20  .02  .05  .06  .01  .04  .20  .06                 150°C.     .04  .11  .015 .04  .04  --   --   .12  .02                 __________________________________________________________________________     ##STR7##                                                                      EXAMPLES 23 AND 24 Preparation of 6-Nylon and 12-Nylon Graft Copolymers  

A Brabender Plastograph was used having a capacity of about 50 grams andheated by circulting oil (temperature 250°C.). Revolving cam-shapedblades kneaded and sheared. A nitrogen blanket was maintained at alltimes.

After 30 grams of the EPDM copolymer-maleic anhydride adduct J, above,had been added, an antioxidant mixture, and oil mixture, and anamino-teminated 6- or 12-nylon (XX or OOO, above) were addedsuccessively as quickly as possible. Mixing then continued for 12minutes. The resulting nylon graft copolymer was dumped. Table XII givesthe properties of a 6-nylon and a 12-nylon graft.

The antioxidant mixture employed (0.7 gram) consisted of 0.3 gram ofN-phenyl-N'-(p-toluenesulfonyl)-p-phenylenediamine [Aranox], 0.3 gram of1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl) benzene[Ethyl Antioxidant 330, formerly Ionox 330], and 0.1 gram of a 7:1weight mixture of potassium iodide and cuprous iodide.

The oil mixture consisted of the antioxidant tris(mono- anddi-nonylphenyl) phoshite ["Polygard" from Uniroyal] and "Sunpar"paraffinic oil 2280 [ASTM D-2226 type 104B, having Saybolt UniversalViscosity values of 2907 sec. and 165 sec. at 37.8°C. and 98.9°C.,respectively; specific gravity, 0.8916 (at 15.6°C.); density, 0.8879g./cc.; molecular weight, 720; viscosity-gravity constant, 0.796;refractive index _(D) ²⁰, 1.4908]. All mixtures contained 0.3 gram ofthe antioxidant; the oil amounted to 10.5 grams for 6-nylon grafting and8.5 grams for 12-nylon grafting.

                  TABLE XII                                                       ______________________________________                                                          6-Nylon   12-Nylon                                          Properties        Graft     Graft                                             ______________________________________                                        Tensile Strength, 97.7      79.4, 66.1                                         kg./sq.cm.                                                                   Extension at Break, %                                                                           680       620, 660                                          Modulus at                                                                    100%  Extension, kg./sq.cm.                                                                         26.7      33.7                                          200%  "               36.6      40.1                                          300%  "               47.1      46.4                                          Permanent Set at Break, %                                                                       40        80                                                Compression Set                                                                (Method B, 22 hrs./70°C.), %                                                            77        83                                                Shore A hardness  66        84                                                Fast Tear, 127 cm./min.,                                                                        11.8      21.4                                               kg./cm.                                                                      ______________________________________                                    

EXAMPLE 25

The ethylene copolymer of Procedure K and the polyamide of Procedure AAwere dissolved in hot hexamethyl phosphoramide. The solutions of thepolymers were mixed to give a ratio of 5 parts of the ethylene copolymerto 1 part of the polyamide. This solution was kept hot for about 5minutes and then poured into rapidly stirred cold acetonitrile toprecipitate the polymer. It was then filtered and washed with acetone toremove excess solvent and dried.

A film was melt pressed at 185°C.

The infrared spectrum showed almost complete reaction of the anydridegroup, indicating that the short polyamide chains had been attached tothe longer ethylene copolymer as side chains.

EXAMPLE 26

Twenty grams of an ethylene copolymer (Procedure L) and 4 g. of apolyamide (Procedure BB) were blended on a two-roll, electrically heatedmill at 175°C. for 5 minutes.

The infrared spectrum of the resultant reaction product showed almostcomplete reaction of the anhydride groups.

EXAMPLES 27 and 28

In a manner similar to Example 25 the polyamides of Procedures HH and IIwere reacted with the ethylene copolymer of Procedure M in a solution ofbenzyl alcohol.

The infrared spectrum showed that over 50% of the anhydride groups hadreacted.

EXAMPLE 29

Thirty grams of polyethylene which was modified by copolymerization with4% maleic anhydride (Procedure N) was blended on a two-roll mill at200°C. with 12 g. of a polyamide (Procedure GG).

The sample was molded at 230°C. to give a clear film. The infraredspectrum showed that over 80% of the anhydride groups had reacted.

EXAMPLES 30 to 36

In a manner similar to Examples 25 and 26 a series of graft polymerswere made using components as shown in Table XIII.

The melting point of Example 32 was found to be 189°C. (by DTAmeasurement).

EXAMPLES 37, 38, 39

Three graft copolymer resins were made by reaction of the molten polymeron a two roll mill at 200°C. for 2 minutes as described in previousexamples. The tensile properties of the graft copolymer are given inTable XIV with a comparison with the ungrafted ethylene copolymers. Thisshows the vastly increased tensile strength imparted to the ethylenecopolymers due to the presence of the polyamide side chains.

                  TABLE XIII                                                      ______________________________________                                               Ethylene                                                               Example                                                                              Copolymer   Polyamide                                                  Number (Procedure) (Procedure)  Blend Method                                  ______________________________________                                        30     26 g.    O      13 g.  GG    Mill 200°C.                        31     40 g.    P       8 g.  MM    Mill 200°C.                        32     40 g.    P       8 g.  NN    Mill 200°C.                        33     26 g.    Q      13 g.  NN    Mill 180°C.                        34      6 g.    R       3 g.  NN    Solution                                                                      Hexamethyl                                                                    Phosphor-                                                                     amide                                     35     25 g.    N      10 g.  OO    Mill 190°C.                        36     26 g.    V      13 g.  GG    Mill 200°C.                        ______________________________________                                    

                                      TABLE XIV                                   __________________________________________________________________________         Ethylene                                                                             Caprolactam                                                       Example                                                                            Copolymer                                                                            Polymer                                                                              Tensile Strength                                                                        Elongation                                       Number                                                                             (Procedure)                                                                          (Procedure)                                                                           Kg./cm..sup.2                                                                          %                                                __________________________________________________________________________    37   U      GG     101.6     555                                                                 27.8 (Control                                                                           1400                                                                Procedure T)                                               38   N      GG     231.3     475                                                                 111.1 (Control                                                                          400                                                                 Procedure M)                                               39   P      GG     141.7     530                                                                 82.3 (Control                                                                           700                                                                 Procedure O)                                               __________________________________________________________________________

EXAMPLES 40 and 41

The value of graft copolymers such as described above in an adhesivesystem is revealed when the adhesive is tested for resistance to failureat elevated temperatures. The use of the graft copolymers of Examples 33and 36 in a hydrogenated wood rosin ester, Hercules' Foral 105 isdescribed below.

Example 40 consists of a blend containing 65% Foral 105 and 35% of thegraft copolymer of Example 33 melt blended on a 2-roll mill at 185°C.This blend was coated on kraft paper using a hot plate and a meyer rod.This coated paper was then sealed to a second, uncoated piece of kraftpaper at 200°C. for 3 seconds at 0.70 kg./sq. cm. pressure. The coatedsandwich was cut into 12.7 mm strips for testing in peel. A 50 g. weightwas used to try to pull the strips apart in peel.

Example 41 consists of a similar blend based on 65% Foral 105 and thegraft copolymer of Example 36. A similar sandwich between pieces ofkraft paper was made, cut, and weighted for testing.

A blend of 65% Foral 105 and a high molecular weight, ungrafted,ethylene/vinyl acetate copolymer, Elvax 260, was made. This was used tobond two pieces of kraft paper for testing as a control for the abovetwo examples. The results are given in Table XV.

                  TABLE XV                                                        ______________________________________                                                     Failure                                                                       Temperature °C., For                                      Sample       Peel of Bonds In Oven                                            ______________________________________                                        Control      65 - 70                                                          Example 41   90 - 95                                                          Example 40   115 - 120                                                        ______________________________________                                    

EXAMPLE 42

Ten grams of an ethylene copolymer (Procedure M) were dissolved in hottoluene. To this hot solution were added 2 ml. of a polyethylene oxideproduct which is a polymer of about 360 molecular weight (about 8ethylene oxide repeat units) and for which most of the chains areterminated on one end by a primary amine (--NH₂) and on the other end byan alkyl group. The material was supplied by Jefferson Chemical Companyand designated amine 4419--35. They report a molecular weight of 360,based on a primary amine content of 2.71 milliequivalents per gram. Theresultant solution was maintained at about 110°C. for 5 minutes. Thesolvent was evaporated and the solid product was melt pressed into aclear film.

The infrared spectrum of this sample showed that essentially all of theanhydride groups of the ethylene copolymer had reacted with the amineends of the polyethylene oxide chains.

EXAMPLE 43

Five grams of an ethylene copolymer (Procedure S) were dissolved in hottoluene. To this hot solution was added 1 gram of the amine terminatedpolyethylene oxide material of Example 42. The solvent was evaporatedand the solid product was melt pressed into a 10 mil film. The film wastested on a Keithly Electrometer No. 610B by ASTM D 257 and found tohave a volume resistivity of 10⁹ ohm cm. In contrast a control,ungrafted ethylene/vinyl acetate copolymer (28% vinyl acetate) had avolume resistivity of 4.4 × 10¹³ ohm cm. Thus, the graft copolymer has aconductivity 44000 times that of the ungrafted resin.

EXAMPLE 44

Five grams of an ethylene copolymer (Procedure R) were reacted with 2 mlof the amine terminated polyethylene oxide polymer of Example 42 and bythe same procedure. The solid film was tested and found to have a volumeresistivity of 6.7 × 10⁷ ohm cm. Thus, this resin has a conductivityalmost 1 million times that of the ungrafted resin in Example 43.

EXAMPLE 45 Preparation of Terminal Amine-Containing Polypivalolactone

To 51.9 g. of 10 percent aqueous tetrabutylammonium hydroxide was added3.02 g. of p-aminophenyl acetic acid. The resulting solution wasevaporated in vacuo to an amber oil which was dried in vacuo to a greensolid which was washed with tetrahydrofuran to give 4.7 g. of nearlycolorless crystals of tetrabutylammonium p-aminophenyl acetate(hygroscopic).

To a stirred solution of 50 g. of pivalolactone in 100 ml. of anhydroustetrahydrofuran in a 500-ml. resin kettle was added a solution of 4.7 g.of tetrabutylammonium p-aminophenyl acetate in 10 ml. of methanol. After5 minutes, an exothermic polymerization occurred with vigorous refluxingand precipitation of polymer. The polymer was collected by filtrationand washed twice with ethanol in a Waring Blendor and dried at 70°/0.1mm. to give 51.7 g. of amine-terminated polypivalolactone, η_(inh) =0.15 (0.5 percent in trifluoroacetic acid, 25°).

Anal. Calcd. for dp 42 C₂₃₄ H₃₈₀ O₈₆ N₂ : C, 61.1; H, 8.35; N, 0.61.Found: C, 61.3; H, 8.28; N, 0.42; C, 60.9; N, 8.26; N, 0.41.

Differential scanning calorimetry: first heating, T_(m) 197°C., T_(m2)200°C.

Grafting Ethylene/Methyl Acrylate/Half Ethyl Ester of Maleic Acid andAmine-Terminated Polypivalolactone

Using a 76.2 mm, two roll roller mill preheated to 225°C., 24 g. ofterminal amine-containing polypivalolactone was first melted (ambercolor) and 41 g. of a copolymer derived from 54 weight percent methylacrylate, 4.5 weight percent half ethyl ester of maleic acid, and 40.5weight percent ethylene. The polymers were rolled for 13 minutes.Initially, vapors were observed, but they soon ceased. Sixty grams ofamber, rubbery polymer were obtained. A film was pressed between Kaptonpolyamide film (Du Pont) at 215°C./14.06 kg./cm.². The film whenstretched at 5.80 cm./min. gave 360 percent elongation at the break (175percent permanent set) with a tensile strength of 133.6 kg./cm.². Asample which was stretched (after cold drawing) 3 times to 160 percenthad 15 percent permanent set. A fiber, spun at 204°C. had a denier of209, an elongation of 200 percent and a tenacity of 0.38 grams perdenier.

A sample of the polymer was purified by grinding in a mill with dry iceand then blending for 1 hour with 300 ml. of ethanol containing 300 ml.of tetrahydrofuran, and 40 ml. of 10 percent hydrochloric acid. Afterwashing in the blender with ethanol, the polymer was dried at 60°C./0.1mm. Purified polymer was pressed into a clear, yellow, bubble-free filmat 200°C./1054.5 kg./cm.² which had 400 percent elongation (100 percentelastic elongation) and a tensile strength of 197.75 kg./cm.².

EXAMPLE 46

Ten grams of an ethylene copolymer (similar to Procedure R) were reactedwith 4 ml of the amine terminated polyethylene oxide polymer of Example42 and by the same procedure.

Four grams of this grafted copolymer were blended with 46 g.polypropylene (Profax 6501, Hercules, Inc.) on an electrically heatedtwo roll mill.

The solid product was melt spun into fiber. The fiber was gathered intoa hank of 3500 denier and tested for resistivity. The fiber resistivitywas 4.8 × 10⁹ ohm cm. This is in contrast to a value of about 10¹⁷ ohmcm. for fiber of pure polypropylene.

EXAMPLE 47

A free radical process, as described in U.S. Pat. No. 3,689,593 was usedto make a polymer of styrene (using aminoethanethiol as the chaintransfer agent). The molecular weight of the polymer is about 3500(about 34 monomer units) and about 90% of the molecules are terminatedwith an NH₂ group on one end with either a phenyl group or a methylgroup on the other end.

0.5 Gram of the solid polymer described above was blended in a solutionof boiling toluene with 2.5 g. of an ethylene copolymer (Procedure S).The solution was used to cast a clear film. The clarity of this filmshows that grafting has taken place.

EXAMPLE 48

Six grams of copolymer similar to that of Procedure M were dissolved inhot toluene. To this were added 3. g. of a low molecular weightpolystyrene similar to that of Example 47. The film was dried on thesteam bath and it dried as a clear film. From the infrared spectra itwas concluded that 20-25 percent of the anhydride present in theethylene copolymer had reacted.

EXAMPLE 49

A low molecular weight polymer of methyl methacrylate was made using theprocess of U.S. Pat. No. 3,689,593. It was made in a 250 ml. roundbottom flask into which was put 100 ml. toluene, 75 ml. of uninhibitedmethyl methacrylate, 0.6 g. of 2-aminoethanethiol and 0.1 g. of (Vazo88) azodicyclohexanecarbonitrile. This was heated with vigorous stirringat 110°C. for 1 hour. Unreacted monomer and solvent was driven off. Theresultant polymer represented a 41 percent conversion of the methylmethacrylate.

Five grams of the ethylene copolymer of Procedure S were dissolved intoluene. To this was added 1.75 g. of the above methyl methacrylatepolymer. The solution was heated to about 100°C. for 10 minutes, dried,and melt pressed into a 0.25 mm film. The film was crystal clear, toughand moderately flexible. A control sample was made by substituting anethylene/vinyl acetate bipolymer containing 28 percent vinyl acetate forthe ethylene copolymer of Procedure S in the above blending procedure.The resultant film was slightly hazy and it exhibited very weak tearstrength. This comparison shows that the low molecular weight polymethylmethacrylate of this Example is not compatible with an ethylene/vinylacetate bipolymer and consequently that the good physical properties ofthis example show that a graft copolymer has been produced.

EXAMPLE 50

A low molecular weight polymer of methyl methacrylate was made by thesame process as Example 49. The level of 2-aminoethanethiol was reducedto 0.4 g. and the temperature was reduced to 100°C. The initiator was0.1 g. Vazo 64 (azobisisobutyronitrile). The resultant polymerrepresented a 51 percent conversion of the methyl methacrylate.

Five grams of the ethylene copolymer of Procedure S were dissolved intoluene. To this was added a toluene solution containing 5.3 g. of theabove polymethyl methacrylate. The solvent was evaporated and thepolymer was pressed at 190°C. into a 0.25 mm film. The film was crystalclear, showing as above that grafting had taken place.

EXAMPLE 51

A blend was made on a heated two roll mill. This blend contained 90percent polyvinyl chloride and 10 percent of the graft copolymer ofExample 50. The polyvinyl chloride used contained 2 percent Thermolite31 as a stabilizer. The blend was molded into slabs 3.17 mm thick fortesting. These were clear. The Izod Impact Strength was 5.4 kg.-cm./cm.of notch. The heat deflection temperature, ASTM D-648 (18.6 kg./cm.²)was 68°C.

EXAMPLE 52

A low molecular weight polymer of methyl methacrylate was made by thesame process as Example 49. The methyl methacrylate level was 47 g., the2-amino-ethanethiol was 0.5 g. and 0.05 g. of Vazo 64(azobisisobutyronitrile) was used as catalyst. The mixture was heated to100°C. for 1 hour. The resultant polymer represented a 36 percentconversion of the methyl methacrylate. The number average molecularweight of the polymer was about 7,000 by vapor pressure osmometry. Thisrepresents an average degree of polymerization of about 70.

EXAMPLE 53

A graft polymer was made as in Example 49. The ingredients were 2 g. ofthe polymer of Example 52 and 2 g. of the polymer of Procedure V. Theproduct was cast from solution into a clear and flexible film, showingthat grafting had taken place.

EXAMPLE 54

A blend was made on a two roll mill. This blend contained 85 percent ofpolyvinyl chloride and 15 percent of the graft copolymer of Example 53.The Izod Impact Strength was 13 kg.-cm./cm. of notch. The value in theVariable Height Impact Test was 122 kg.-cm./mm of thickness (0.76 mmsheet).

EXAMPLE 55

A low molecular weight polymer was made as in Example 49. Theingredients were 47 g. of methyl methacrylate, 0.4 g. of2-aminoethanethiol and 0.04 g. of Vazo 64. The resultant polymerrepresented a 33 percent conversion of the methyl methacrylate. Thenumber average molecular weight was 5500 by vapor pressure osmometry.

EXAMPLE 56

A graft copolymer was made as in Example 49. The ingredients were 2.4 g.of the polymer of Example 55 and 3.7 g. of a polymer containing 32percent vinyl acetate and 2.6 percent maleic anhydride. The film wasclear and rubbery. The infrared spectrum showed that essentially all ofthe anhydride groups were reacted.

EXAMPLE 57

A blend was made as in Example 51. The components were 85 percentpolyvinyl chloride and 15 percent of Example 56. The flexural modulus ofthis blend was 23,902 kg./sq. cm.; the Izod Impact Strength 12kg.-cm./cm of notch; the Variable Height Impact Test value 122kg.-cm./mm and the Heat Deflection Temperature, 69°C.

EXAMPLE 58

Five grams of an ethylene copolymer containing maleic anhydride,Procedure Q, were dissolved in toluene. To this solution were added 2 g.of a polypropylene oxide substantially all of the chains of which havean alkyl group of 3 carbon atoms on one end and a primary amine on theother end. (Supplied by Jefferson Chemical Company as Jeffamine4419--69; molecular weight approximately 600). The solvent was removedby heating over a steam bath. A film of this product cast from solutionwas clear, indicating that grafting had taken place.

EXAMPLE 59

One gram of the ethylene copolymer of Procedure S was dissolved in hothexamethyl phosphoramide, one-half g. of a low molecular weightpolycaprolactam of Procedure GG was also dissolved in hot hexamethylphosphoramide. The two solutions were mixed and kept hot for about 5minutes. The polymer was precipitated in pentane, filtered, washed withpentane and dried. The melt pressed film from this polymer was clear.The infrared spectrum showed that about 50 percent of the anhydridegroups of the ethylene copolymer had reacted.

One gram of the above half-grafted copolymer was redissolved in hothexamethyl phosphoramide. To this solution was added one-half g. of theshort chain polyethylene oxide of Example 42. This was again held hotfor about 5 minutes, precipitated, filtered, washed and dried. Theinfrared scan showed that all of the anhydride was reacted by theabsence of the infrared band at 5.4 microns.

In this example, there has been produced a graft copolymer in which themain chain is an ethylene/vinyl acetate/maleic anhydride copolymer, andwhich has two types of side chains; one is a polyamide chain, the otheris a chain of polyethylene oxide units.

EXAMPLE 60

Hot toluene was used as the reaction medium in which a short chain ofpolymethyl methacrylate units similar to the product in Example 49 weregrafted to the ethylene copolymer of Procedure S. The dried sample waspressed into a clear film. The infrared spectrum showed that about 10percent of the anhydride groups had reacted.

0.75 Gram of this graft copolymer was redissolved in toluene. To thiswas added 0.25 g. of the short chain polyethylene oxide material ofExample 42. This solution was kept hot for 5 minutes and then dried. Thepressed film was clear, and the infrared spectrum showed completereaction of the anhydride.

In this example, there has been produced a graft copolymer in which themain chain is an ethylene/vinyl acetate copolymer/maleic anhydride, andwhich has two types of side chains, one is a polymethyl methacrylatechain, the other is a polyethylene oxide chain.

EXAMPLE 61

In a manner similar to the procedure in Example 60, 0.5 g. of a shortchain polystyrene similar to that described in Example 47 was grafted to1 g. of the ethylene copolymer of Procedure S. To 0.75 g. of thispartially grafted copolymer was grafted 0.25 g. of the polyethyleneoxide of Example 42.

In this example there has been made a graft copolymer in which the mainchain is an ethylene/vinyl acetate/maleic anhydride copolymer, some ofthe side chains are polystyrene and others are polyethylene oxidechains.

EXAMPLE 62

In a manner similar to the procedure of Example 60, 2 g. of thepolymethyl methacrylate resin of Example 49 was reacted with 1 g. of theethylene copolymer of Procedure S. The infrared spectrum of thiscopolymer showed that about 40 percent of the anhydride had reacted.

To 11/2 g. of this partially grafted copolymer was grafted 1 g. of theshort chain polystyrene resin similar to that described in Example 47.The film pressed from this graft copolymer was clear. The infraredspectrum showed that about 90 percent of the anhydride graft sites hadreacted.

In this example there was made a graft copolymer in which about 50percent of the total number of side chains are polymethyl methacrylatechains and about 50 percent of the total number of side chains arepolystyrene side chains.

EXAMPLE 63

An ethylene copolymer was synthesized and was shown by analysis to have23 percent vinyl acetate and 9 percent methyl hydrogen maleate (the halfmethyl ester of maleic acid).

A toluene solution was made of 1.5 g. of this copolymer and 1 g. of anamine terminated polyethylene oxide of about 1000 molecular weight. Thisis similar to the polyethylene oxide of Example 42. This solution washeated for about 15 minutes and then heat treated on a steam bath todrive off the solvent. The infrared spectrum showed that grafting hadtaken place.

EXAMPLE 64

A styrene copolymer containing 17 percent by weight copolymerized maleicanhydride was obtained from Monsanto (Lyntron 820). Two grams of thiscopolymer were reacted in solution the solvent beingtoluene/tetrahydrofuran (90/10) with 3.6 g. of the amine-terminatedpolyethylene oxide (molecular weight 1000) of Example 63. The driedblend is perfectly clear, indicating that grafting has taken place.

EXAMPLE 65

Two grams of the styrene-maleic anhydride copolymer of Example 64 werereacted in solution as described in that Example with 2.2 g. of theamine-terminated polypropylene oxide (mol. wt. 600) of Example 60. Thedried blend is perfectly clear, indicating that grafting has takenplace.

EXAMPLE 66

One gram of the styrene/maleic anhydride copolymer of Example 64 wasreacted in solution the solvent being hexamethylphosphoramide with anamine-terminated polycaprolactam oligomer of mol. wt. 1140 (ProcedureDD). The resultant polymer gave a clear film, indicating that graftinghas taken place.

(Ethylene/Maleic Anhydride)/Caprolactam Graft Copolymer

A. solution Procedure

EXAMPLE 67

A solution of 10 g. of 95.8/4.2 ethylene/maleic anhydride (E/MAnh)copolymer (MI = 15) in 125 ml. toluene and 25 ml.hexamethylphosphoramide (HMP) was mixed with a solution of 3.7 g. ofcaprolactam (CL)/hexylamine (HA) oligomer (DP = 7; Table VIII, ProcedureFFF in 100 ml. of dry HMP at 105°C. and the mixture was stirred andheated at 100°-110°C. for 1 hr. The reaction mixture was then partiallycooled and the polymeric product precipitated and isolated by addingsuccessively two 15-ml. portions of methanol, the mixture was cooled toroom temperature and diluted with 300 ml. of methanol to precipitate thegraft copolymer. The polymer was isolated by filtration and then washedsuccessively in a blender twice with methanol, twice with water, andthen twice with methanol. The vacuum-dried product (11.2 g.) showed DSCmelting endotherms at 106° (olefin peak) and 187° (amide peak), and wasmolded into a 0.13 mm film which was clear, transparent and flexible,indicating that an (E/MAnh)/CL graft copolymer had been formed. The filmhad a tensile strength (T) of 143 kg./cm.², an elongation (E) of 280percent and a modulus (M) of 1930 kg./cm.², and molded bars gaveflexural modulus (FM) kg./cm.² of 2600 at 25°, 1270 at 60° and 548 at100°. Nitrogen analysis indicated a CL/HA content of 21 percent byweight.

The above procedure was repeated with 10 g. of the 95.8/4.2 E/MAnhcopolymer (MI = 15) and 7.3 g. of the CL/HA oligomer (DP = 15) of TableVIII, Procedure BBB. The resulting (E/MAnh)/CL graft copolymer analyzedfor 40 percent CL/HA; had DSC melting endotherms at 106° and 207°; in0.13 mm film showed T = 178 kg./cm.², E = 87 percent and M = 4060kg./cm.² ; and molded bars gave flexural modulus kg./cm.² values of 6190at 25°, 2390 at 60° and 1400 at 100°C.

B. roll Mill Procedure (Melt Reaction)

EXAMPLE 68

A 40-g. sample of 95.8/4.2 E/MAnh copolymer (MI = 15) was worked under astream of nitrogen on a 2-roll mill with electrically heated 76.2 mmrolls heated to 205° until the copolymer was molten. Finely dividedCL/HA oligomer (9.7 g.; DP = 10; prepared as in Table VIII, ProcedureDDD) was sprinkled into the molten polymer and milling continued forabout 6 minutes. The milled product (48 g.) was then removed and cooled.Analysis showed a CL/HA content of 19 percent by weight. It formedpressed 0.13 mm films at 240°-260° which were clear, transparent,pliable and creasable, and which showed presence of amide and anhydridestructure by infrared spectroscopy. Film tests showed T of 135 kg./cm.²,E of 306 percent and M of 2180 kg./cm.².

The above procedure was repeated with the same E/MAnh copolymer, variousCL/HA oligomers and different mill temperatures. All of the productsgave clear, transparent films, indicating positive formation of grafted(E/MAnh)/(CL/HA) copolymer. The data are presented in Table XVI.

                                      TABLE XVI                                   __________________________________________________________________________    Milled (Ethylene/Maleic Anhydride)/Caprolactam Graft Copolymers                         CL/HA Oligomer                        FM   DSC                           E/MAnh             Temp. CL/HA.sup.b                                                                        T   E   M    kg./cm..sup.2                                                                      peaks.                   Ex. 68                                                                             (g)  (I-Ex.).sup.a                                                                       (g) (DP)                                                                              (°C)                                                                         (%)  kg/cm.sup.2                                                                       %   kg./cm..sup.2                                                                      25°                                                                         (°C.)             __________________________________________________________________________    A    40.0 AAA   8.0  7  190   16(17)                                                                             --  --  --   2250 107, 108                 B.sup.c                                                                            30.0 AAA   11.1                                                                               7  210-215                                                                             25(27)                                                                             146 230 2240 2460 108, 185                 C    30.0 BBB   22.0                                                                              15  220-225                                                                             40(42)                                                                             173  73 4290 4430 109, 207                 D.sup.c                                                                            30.0 --    29.1                                                                              20  225-230                                                                             (49) 214 116 4150 5690 --                       E.sup.c                                                                            30.0 --    29.1                                                                              20  240   (49) 190  75 4400 6260 --                       F.sup.c                                                                            30.0 --     9.8                                                                               5.8                                                                              190-200                                                                             (25) 155 360 2080 2390 --                       __________________________________________________________________________     .sup.a From Table VIII.                                                       .sup.b Based on % N in milled product. Values in () are from quantities       charged.                                                                      .sup.c Base polymer and oligomer premixed before placing on mill.        

C. extrusion Procedure (Melt Reaction)

EXAMPLE 69

A 65/35 mixture of 93.8/6.2 E/MAnh copolymer (MI = 5.1) and CL/HAoligomer (DP = 7; Table VIII, Procedure AAA) was put through a twinscrew mixing extruder at 225°, the throughput time being about 4minutes. The extrudate was a clear melt, indicating that the graftingreaction had gone well in a single pass. The product showed a flexuralmodulus of 2030 kg./cm.². Torsion modulus values (dynes/cm² × 10⁻ ⁹) atvarious temperatures were as follows: 12.4 at -180°; 8.0 at -100°; 5.1at -50°; 2.3 at 0°; 1.37 at 20°; 0.61 at 50°; 0.16 at 100°; 0.08 at150°.

The above procedure was used to prepare additional (E/MAnh)/CL graftcopolymers, the data being presented in Table XVII.

                                      TABLE XVII                                  __________________________________________________________________________    Extruded (Ethylene/Maleic Anhydride)/Caprolactam Graft Copolymers              E/MAnh                                  Torsion Modulus, dynes/cm.sup.2                                               × 10.sup.-.sup.9                        MAnh.sup.a                                                                          E/MAnh.sup.b                                                                         CL/HA Oligomer                                                                            Flex. Mod.                                                                           -180                                                                             -100                                                                             -50                                                                              0 20                                                                              50 100                                                                              150               Ex. 69                                                                             MI  (%)   (%)    Proc.                                                                             (DP)                                                                              (%).sup.b                                                                         (kg./cm..sup.2)                                                                      °C.                                                                       °C.                                                                       °C.                                                                       °C.                                                                      °C.                                                                      °C.                                                                       °C.                                                                       °C.        __________________________________________________________________________    A    126 9.8   54     AAA  7  46  2810   12.0                                                                             8.1                                                                              6.0                                                                              3.0                                                                             2.1                                                                             0.88                                                                             0.34                                                                             0.21              B    5.7 5.9   44     --  18  56  --     15.5                                                                             9.5                                                                              7.4                                                                              5.0                                                                             4.0                                                                              2.8                                                                             0.70                                                                             0.40              C    136 9.4   34     --  18  66  --     16.0                                                                             9.1                                                                              7.1                                                                              5.0                                                                             4.0                                                                              2.6                                                                             0.72                                                                             0.38              __________________________________________________________________________     .sup.a Percent MAnh in the substrate E/MAnh copolymer.                        .sup.b Percent of reactant in the extrusion mixture.                     

EXAMPLE 70 (Ethylene/Ethyl Maleate)/Caprolactam Graft Copolymer

A mixture of 18 g. of 91/9 ethylene/monoethyl ester of maleic acid(E/MAME) copolymer and 5.1 g. of CL/HA oligomer (DP = 6.7) was milled ona two roll mill as in Example 68. The resulting (E/MAME)/CL graftcopolymer could be rolled out in a cold mill to form a flexible sheet.It analyzed for a CL/HA content of 22 percent. Torsion modulus values(dynes/cm.² × 10.sup.⁻⁹) at various temperatures: 11.9 at -180°; 9.4 at-100°; 8.2 at -50°; 5.2 at 0°; 3.8 at 20°; 2.6 at 50°; 0.90 at 100°;0.14 at 150°.

EXAMPLE 71 (Ethylen/Butyl Itaconate)/Caprolactam Graft Copolymer

Following generally the solution procedure of Example 67, 7 g. of88.3/11.7 ethylene/monobutyl ester of itaconic acid (E/BuIt) copolymerwas dissolved in 100 ml. of toluene at 100°-115°, 25 ml. of HMP wasadded, and then a solution of 3.7 g. of CL/HA oligomer (DP = 6.7) in 75ml. of HMP was added in one portion with vigorous stirring. Stirring andheating was continued for 1.25 hours, and the graft copolymer was thenprecipitated and isolated through addition of 400 ml. of methanol. Theproduct (8.2 g.) analyzed for a CL/HA content of 23 percent by weight.Films pressed at 235°-240° were clear, transparent and flexible.

(Ethylene/Maleic Anhydride)/Laurolactam Graft Copolymer EXAMPLE 72

Following the solution procedure of Example 67, a series of (E/MAnh)/LLgraft copolymers was prepared. The data are given in Table XVIII.

                                      TABLE XVIII                                 __________________________________________________________________________    (E/MAnh)/LL Graft Copolymers                                                  Base Polymer     LL/HA Oligomer                                                                              Graft Copolymer                                     MAnh                      Yield                                                                             LL/HA                                                                              DSC                                   Ex. 72                                                                             (%) MI  (g) (Proc.)                                                                            (DP)                                                                              (g)  (g) (%)  Mp (°C)                                                                      FM (kg./cm..sup.2)              __________________________________________________________________________    A    9.8 174  7.0                                                                              MMM  6.5 9.6  14.8                                                                              --   160   --                              B    6.2 5   10.0                                                                              MMM  6.5 8.7  17.1                                                                              --   160   --                              C    4.2 15  10.0                                                                              NNN  7.2  6.54                                                                              14.9                                                                              39   163-5 --                              D    3.0 40  10.0                                                                              NNN  7.2  4.55                                                                              13.0                                                                              31   --    --                              E    3.0 40  10.0                                                                              --   6.4 2.5  10.7                                                                              18   160   2900                            F    3.0 40  10.0                                                                              --   6.4 1.5  10.2                                                                              14   159   3070                            __________________________________________________________________________

EXAMPLE 73

An ethylene/maleic anhydride trunk copolymer was prepared whichcontained 86.5 weight percent ethylene and 13.5 weight percent maleicanhydride. The copolymer was pumped by an extruder through a tube heatedto about 500°C. to reduce the molecular weight. The melt viscosity was600 centipoises at 140°C. The average chain length was about 300 carbonatoms.

One gram of the trunk copolymer was reacted with 2 g. of theamine-terminated caprolactam/laurolactam oligomer of Procedure 00 in hothexamethylphosphoramide. The solution was kept hot for about 5 minutesand then poured into rapidly stirred cold pentane to precipitate thepolymer. It was then filtered and washed with acetone to remove excesssolvent and dried.

The trunk copolymer of the graft copolymer averages only about 3amine-active sites per chain. The chain length of side chain polymeraverages about two-thirds the length of the trunk copolymer. On theaverage three side chain polymers are attached to the trunk copolymer.

We claim:
 1. Process for the preparation of thermoplastic graftcopolymers which comprises heating for about 15 seconds to 60 minutes,with mixing, (1) a trunk copolymer of at least two monomers, at leastone of said monomers providing amine-reactive sites taken from the groupconsisting of an anhydride group, a vicinal pair of carboxylic groupsand a carboxylic group adjacent to an alkoxycarbonyl group, wherein thealkoxy group contains up to 20 carbon atoms, and at least one of saidmonomers containing no aminereactive sites, and (2) at least one sidechain polymer, ranging in length from about 25 to 1000 chain atoms,having per chain one active amine site taken from the group consistingof primary and secondary amines, the remainder of said side chainpolymer being substantially unreactive with the reactive sites of thetrunk copolymer.
 2. A process according to claim 1 wherein the activeamine site of the side chain polymer is a primary amine.
 3. A processaccording to claim 1 wherein the process is conducted in the melt.
 4. Aprocess according to claim 1 wherein the process is conducted insolution.
 5. A process according to claim 1 wherein the heatingtemperature is above the melting points of the trunk copolymer and sidechain polymer.
 6. A process according to claim 1 wherein the heating isconducted for about 15 seconds to 10 minutes.
 7. A process according toclaim 1 wherein the trunk copolymer is derived from an α-olefin and atleast one monomer providing amine-reactive sites taken from the groupconsisting of an anhydride, diacid and half-esters derived therefrom. 8.A process according to claim 7 wherein the α-olefin is ethylene.
 9. Aprocess according to claim 8 wherein there is present at least oneadditional polymerizable monomer which contains no amine-reactive sitesand no anhydride reactive sites.
 10. A process according to claim 9wherein the additional polymerizable monomer is 3-methylbutene.
 11. Aprocess according to claim 9 wherein the additional polymerizablemonomer is vinyl acetate.
 12. A process according to claim 9 wherein theadditional polymerizable monomer is methyl acrylate.
 13. A processaccording to claim 9 wherein the additional polymerizable monomer ismethyl methacrylate.
 14. A process according to claim 1 wherein thetrunk copolymer is derived from styrene and at least one monomerproviding amine-reactive sites taken from the group consisting of ananhydride, diacid and half-esters derived therefrom.
 15. A processaccording to claim 14 wherein there is present at least one additionalpolymerizable monomer containing no amine-reactive sites and noanhydride reactive sites.
 16. A process according to claim 7 wherein themonomer providing amine-reactive sites is maleic anhydride wherein themaleic anhydride is present in an amount of 1.0 to 25.0 parts by weight.17. A process according to claim 14 wherein the monomer providingamine-reactive sites is maleic anhydride wherein the maleic anhydride ispresent in an amount of 1.0 to 30.0 parts by weight.
 18. A processaccording to claim 9 wherein the trunk copolymer is composed ofethylene, monoalkyl maleate, wherein alkyl is in the range of 1 to 4carbon atoms, in addition to an additional polymerizable monomer.
 19. Aprocess according to claim 9 wherein the trunk copolymer is composed ofethylene, monoalkyl fumarate wherein alkyl is in the range of 1 to 4carbon atoms, in addition to an additional polymerizable monomer.
 20. Aprocess according to claim 9 wherein the trunk copolymer is composed ofethylene, monoalkyl itaconate wherein alkyl is in the range of 1 to 4carbon atoms, in addition to an additional polymerizable monomer.
 21. Aprocess according to claim 1 wherein the side chain polymer is selectedfrom the group consisting of polymers of lactams containing 3 to 12carbon atoms, copolymers of lactams containing 3 to 12 carbon atoms,polymers of organic oxides containing 2 to 16 carbon atoms, copolymersof organic oxides containing 2 to 16 carbon atoms, polymers of styrene,polymers of substituted styrenes, copolymers of styrene and substitutedstyrene, polymers of acrylates, polymers of methacrylates, copolymers ofacrylates and methacrylates, and polymers of lactones.
 22. A processaccording to claim 21 wherein a side chain polymer present is apolycaprolactam.
 23. A process according to claim 21 wherein a sidechain polymer present is a polylaurolactam.
 24. A process according toclaim 21 wherein a side chain polymer present is a copolymer ofcaprolactam and laurolactam.
 25. A process according to claim 21 whereina side chain polymer present is polyethylene oxide.
 26. A processaccording to claim 21 wherein a side chain polymer present ispolypropylene oxide.
 27. A process according to claim 21 wherein a sidechain polymer present is polystyrene.
 28. A process according to claim21 wherein the side chain polymers are short chains having repeat unitsfrom about 5 to 50 in which at least 80 percent of the side chainpolymers have one active amine site and the remainder of said side chainpolymer is substantially unreactive with the amine-reactive sites on thetrunk copolymer.
 29. A process according to claim 28 wherein the sidechain polymers contain substituent alkyl groups of 1 to 18 carbon atoms.30. A process according to claim 28 wherein the side chain polymerscontain substituent aryl groups.
 31. A process according to claim 1wherein the trunk copolymers contain, on the average, about 300 to50,000 chain atoms and the number of reactive sites occur, on theaverage, at a frequency of 1 to 50 sites per thousand chain atoms of themain chain.
 32. A process according to claim 31 wherein trunk copolymerscontain, on the average, about 500 to 2,000 chain atoms of the mainchain.
 33. A process according to claim 31 wherein the side chainpolymer reactive with the amine-reactive sites on the trunk copolymerrange in length from 25 to 1,000 chain atoms.
 34. A thermoplastic graftcopolymer consisting essentially of a trunk copolymer derived from atleast two monomers, at least one of said monomers providingamine-reactive sites selected from the group consisting of an anhydridegroup, a vicinal pair of carboxylic groups and a carboxylic groupadjacent to an alkoxycarbonyl group, wherein the alkoxy group containsup to 20 carbon atoms, and at least one of said monomers containing noamine-reactive sites; and at least one type side chain polymer linked tosaid reactive sites through amide or imide linkages, said side chainpolymer being derived from a short chain polymer having from about 5 to50 repeat units and containing one active amine site selected from thegroup consisting of primary and secondary amines, the remainder of theside chain polymer being substantially unreactive with theamine-reactive sites of the trunk copolymer, with the proviso that whenonly one type of side chain polymer is present the side chain polymercontains only one nitrogen atom, said atom being found in the activeamine site.
 35. A graft copolymer according to claim 34 wherein thetrunk copolymer and side chain polymers are linked through imidelinkages.
 36. A graft copolymer according to claim 34 wherein solely onetype of side chain polymer is linked to the trunk copolymer, said sidechain polymer being selected from the group consisting of polymers oforganic oxides containing 2 to 16 carbon atoms, copolymers of organicoxides containing 2 to 16 carbon atoms, polymers of styrene, polymers ofsubstituted styrenes, copolymers of styrene and substituted styrene,polymers of acrylates, polymers of methacrylates, copolymers ofacrylates and methacrylates, and polymers of lactones.
 37. A graftcopolymer according to claim 36 wherein the side chain polymer ispolyethylene oxide.
 38. A graft copolymer according to claim 36 whereinthe side chain polymer is polypropylene oxide.
 39. A graft copolymeraccording to claim 36 wherein the side chain polymer is apolymethacrylate.
 40. A graft copolymer according to claim 36 whereinthe side chain polymer is a polyacrylate.
 41. A graft copolymeraccording to claim 36 wherein the side chain polymer is polystyrene. 42.A graft copolymer according to claim 34 wherein at least two differenttype side chain polymers are present.
 43. A graft copolymer according toclaim 42 wherein the side chain polymers are selected from the groupconsisting of polymers of lactams containing 3 to 12 carbon atoms,copolymers of lactams containing 3 to 12 carbon atoms, polymers oforganic oxides containing 2 to 16 carbon atoms, copolymers of organicoxides containing 2 to 16 carbon atoms, polymers of styrene, polymers ofsubstituted styrenes, copolymers of styrene and substituted styrene,polymers of acrylates, polymers of methacrylates, copolymers ofacrylates and methacrylates, and polymers of lactones.
 44. A graftcopolymer according to claim 43 wherein the side chain polymers arepolyethylene oxide and polycaprolactam.
 45. A graft copolymer accordingto claim 43 wherein the side chain polymers are polyethylene oxide andpolymethyl methacrylate.
 46. A graft copolymer according to claim 43wherein the side chain polymers are polystyrene and polyethylene oxide.47. A graft copolymer according to claim 43 wherein the side chainpolymers are polystyrene and polymethyl methacrylate.
 48. A graftcopolymer according to claim 34 wherein the trunk copolymer is derivedfrom ethylene and at least one monomer providing amine-reactive sitestaken from the group consisting of an anhydride, diacid and half-estersderived therefrom.
 49. A graft copolymer according to claim 48 whereinthere is present at least one additional polymerizable monomer whichcontains no amine-reactive sites and no anhydride reactive sites.
 50. Agraft copolymer according to claim 48 wherein the side chain ispolyethylene oxide.
 51. A graft copolymer according to claim 48 whereinthe side chain is a polymer selected from the group consisting ofpolyacrylate, polymethacrylate or copolymers thereof.
 52. A graftcopolymer according to claim 48 wherein the monomer providingamine-reactive sites is maleic anhydride wherein the maleic anhydride ispresent in an amount of 1.0 to 25 parts by weight.
 53. A graft copolymeraccording to claim 34 wherein the trunk copolymer is derived fromstyrene and at least one monomer providing amine-reactive sites takenfrom the group consisting of an anhydride, diacid and half-estersderived therefrom.
 54. A graft copolymer according to claim 53 whereinthere is present at least one additional polymerizable monomercontaining no amine-reactive sites and no anhydride reactive sites. 55.A graft copolymer according to claim 53 wherein the monomer providingamine-reactive sites is maleic anhydride wherein the maleic anhydride ispresent in an amount of 1.0 to 30 parts by weight.
 56. A graft copolymeraccording to claim 49 wherein the trunk copolymer is composed ofethylene, monoalkyl maleate, wherein alkyl is in the range of 1 to 4carbon atoms, in addition to an additional polymerizable monomer.
 57. Agraft copolymer according to claim 49 wherein the trunk copolymer iscomposed of ethylene, monoalkyl fumarate wherein alkyl is in the rangeof 1 to 4 carbon atoms, in addition to an additional polymerizablemonomer.
 58. A graft copolymer according to claim 49 wherein the trunkcopolymer is composed of ethylene, monoalkyl itaconate wherein alkyl isin the range of 1 to 4 carbon atoms, in addition to an additionalpolymerizable monomer.
 59. A graft copolymer according to claim 34wherein the trunk copolymer contains, on a number average, about 300 to50,000 chain atoms and the number of reactive sites occur, on theaverage, at a frequency of about 1 to 200 reactive sites per thousandchain atoms of the trunk copolymer, there being on the average at leastabout one active site per trunk copolymer chain.
 60. A graft copolymeraccording to claim 59 wherein the trunk copolymer contains, on theaverage, about 500 to 2,000 chain atoms.
 61. A graft copolymer accordingto claim 59 wherein any side chain polymer reactive with theamine-reactive sites on the trunk copolymer range in length from 25 to1,000 chain atoms.
 62. A process according to claim 1 wherein the sidechain polymer has an average degree of polymerization of 5 to
 60. 63. Aprocess according to claim 62 wherein the average degree ofpolymerization of the side chain polymer is 6 to
 8. 64. A graftcopolymer according to claim 34 wherein the side chain polymer has anaverage degree of polymerization of 5 to
 60. 65. A graft copolymeraccording to claim 64 wherein the average degree of polymerization ofthe side chain polymer is 6 to
 8. 66. A graft copolymer according toclaim 64 wherein the non-reactive end of the side chain polymer hassubstituent alkyl groups of 1 to 18 carbon atoms.
 67. A graft copolymeraccording to claim 64 wherein the non-reactive end of the side chainpolymer has substituent aryl groups.